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=========================================================== MM MM IIIIIII CCCC RRRRRR OOO CCCC M M M M I C C R R O O C C M M M I C R R O O C M M I C RRRRRR O O ----- C M M I C R R O O C M M I C C R R O O C C M M IIIIIII CCCC R R OOO CCCC =========================================================== A compact 'C' compiler for small systems. Library Reference Release 2.2 Revised 24-Jan-92 Copyright 1988,1992 Dave Dunfield All rights reserved MICRO-C Library Page: 1 1. THE MICRO-C LIBRARIES The MICRO-C distribution disk includes the 'C' and 'ASM' source code for a very complete function library which is configured for use on an IBM/PC under the MS-DOS operating system. These routines may be also be used as "example" programs, providing insight into MICRO-C programming techniques. All functions except for the lowest level I/O routines are coded in 'C', and should compile on any MICRO-C system. Note that some low level functions in the library are written in 'C' using still lower level routines. Although this makes the library highly portable and reduces the number of routines you have to re-write for a specific system, the resultant function will be less efficent than one which directly uses the operating system services. If you are implementing MICRO-C an a small system and intend to use it for serious programming, I strongly recommend that you re-code all of the low level library functions in assembly language. Note that since library routines are often used in applications where code size and execution speed are of primary importance, it may be desirable to recode some or all of the other library routines in assembly language as well. For those who intend to make only casual use of MICRO-C, or who wish to experiment with it simply for the learning experience, the 'C' versions of the low level library functions should be more than sufficient. NOTE: If you purchased MICRO-C as part of a "developers kit", refer to the documentation included with the CPU support files for details on the pre-configured library for that CPU, and the functions available therein. MICRO-C Library Page: 2 +----------------------------+ | | | ************************ | | * The STANDARD library * | | ************************ | | | +----------------------------+ 1.1 STANDARD Library The library functions described on the following pages are currently available in the IBM/PC MICRO-C library as "standard" functions which are of a general nature, and should be portable to most implementations of MICRO-C. The exact syntax and capabilities of the system or processor dependant functions may vary in different implementations, see your implementation notes (READ.ME) for details. Different possible forms of such functions are shown using (1), (2), ... In these cases, the form (1) of the function is the one used in the MS-DOS library. ABORT ABORT PROTOTYPE: abort(char *message) ARGUMENTS: message - Pointer to message to display RETURN VALUE: N/A - Function never returns DESCRIPTION: This function writes the string passed as an argument to standard error, and then terminates the program with a return code of '-1' (Indicating general failure). This provides a simple method of terminating a program on an error condition with a message explaining why. EXAMPLES: abort("Invalid operand\n"); ABS ABS PROTOTYPE: int abs(int number) ARGUMENTS: number - Any integer value RETURN VALUE: The absolute value of "number" DESCRIPTION: The "abs" function returns the absolute value of the argument. If "number" is a positive value, it is returned unchanged. If negative, the negate of that value is returned (giving a positive result). EXAMPLES: difference = abs(value1 - value2); ATOI ATOI PROTOTYPE: int atoi(char *string) ARGUMENTS: string - Pointer to a string containing a decimal number RETURN VALUE: 16 bit integer value DESCRIPTION: The "atoi" function converts an ASCII string containing a signed decimal number (-32768 to 32767) to a 16 bit value which is returned. An unsigned number of the range (0 to 65535) may also be used, and the result if assigned to an "unsigned" variable will be correct. EXAMPLES: value = atoi("1234"); value = atoi("-1"); CD CD PROTOTYPE: int cd(char *pathname) ARGUMENTS: pathname- Name of directory to make current RETURN VALUE: 0 if successful, otherwise an operating system error code DESCRIPTION: This function sets the "current" directory, causing all subsequent file references which do not explicitly indicate a directory path to access the path specified by "pathname". EXAMPLES: cd("/mc/c_source"); /* UNIX */ cd("\\mc\\l_source"); /* MS-DOS */ CLOSE CLOSE PROTOTYPE: close(HANDLE fh); ARGUMENTS: fh - File handle of an open file RETURN VALUE: None DESCRIPTION: This function closes a file which was previously opened using "open". EXAMPLES: close(fh); CONCAT CONCAT PROTOTYPE: register concat(char *dest, char *source, ...) ARGUMENTS: dest - Pointer to destination string source - Pointer to source string ... - Additional sources may be given RETURN VALUE: None DESCRIPTION: The "concat" function concatinates the given source strings into one destination string. The destination string must be large enough to hold all of the source strings plus the string terminator (zero) byte. No value is returned. NOTE: This function uses a variable number of arguments, and must be declared as "register" (See "stdio.h"). EXAMPLES: concat(filename,"/tmp/", input_name); CREATE CREATE PROTOTYPE: int create(char *pathname, int attrs) ARGUMENTS: pathname- Name of file to create attrs - Attributes for new file RETURN VALUE: 0 if successful, otherwise an operating system error code DESCRIPTION: The "create" function creates a new file with the specified system attributes. The meaning of the individual bits in the "attrs" value is system dependant, and is defined in the "file.h" header file. EXAMPLES: create("temp", HIDDEN); DELETE DELETE PROTOTYPE: int delete(char *pathname) ARGUMENTS: pathname- Name of file to delete RETURN VALUE: 0 if successful, otherwise an operating system error code DESCRIPTION: The "delete" function removes an existing file from the disk. Any disk space occupied by the file is released. EXAMPLES: delete("temp"); EXIT EXIT PROTOTYPE: exit(int rc); ARGUMENTS: rc - Termination return code RETURN VALUE: N/A - Function never returns DESCRIPTION: This function terminates the execution of the program and passes a specific return code back to the operating system. A return code value of zero is used to indicate successful program completion. Non-zero return code values may be used to indicate a particular type of failure. A value of '-1' is often used to indicate a non-specific failure. Note that the "rc" value is very system specific, in particular, some systems support only 8 bit return codes, so values which are greater than 255 should be avoided. EXAMPLES: exit(0); /* success */ exit(-1); /* failure */ FCLOSE FCLOSE PROTOTYPE: fclose(FILE *fp); ARGUMENTS: fp - File pointer to an open file RETURN VALUE: None DESCRIPTION: This function closes a file which was previously opened using "fopen". The I/O buffer space used by the file is released. In the case of a file open for write ('w'), the last disk buffer is flushed and written to disk. EXAMPLES: fclose(fp); FFLUSH FFLUSH PROTOTYPE: fflush(FILE *fp) ARGUMENTS: fp File pointer to an open file RETURN VALUE: 0 if successful, otherwise an operating system error code DESCRIPTION: The "fflush" function flushes the I/O buffers for the given open file. If the file is opened for WRITE, this causes any data remaining in a partially filled output buffer to be written. If the file is opened for READ, this has the effect of throwing away any data which is pending in the input buffer. EXAMPLES: fputs("Enter you name?", stdout); fflush(stdout); /* Make sure prompt is output */ fgets(name, 80, stdin); FGETS FGETS PROTOTYPE: char *fgets(char *buffer, int size, FILE *fp) ARGUMENTS: buffer - Pointer to string to receive line size - Maximum size of line to read fp - File pointer to an input file RETURN VALUE: Pointer to "buffer", or 0 if end of file DESCRIPTION: The "fgets" function reads characters from the specified input file, and places them in the character buffer until one of three things happens: 1) A NEWLINE character is encountered. 2) The END of the file is encountered. 3) The limit of "size" character is read. The string is terminated with the standard NULL (00) character. The trailing NEWLINE '\n' character is NOT included in the output buffer. EXAMPLES: fgets(input_line, 80, input_file); FIND_FIRST FIND_FIRST PROTOTYPE: int find_first(char *pattern, int mattrs, char name[], int &sizeh, int &sizel, int &attrs, int &time, int &date) ARGUMENTS: pattern - File name pattern to match mattrs - File attributes to match name - Address of string to receive file name &sizeh - Address of int to receive high word of size &sizel - Address of int to receive low word of size &attrs - Address of int to receive attributes &time - Address of int to receive time stamp &date - Address of int to receive date stamp RETURN VALUE: 0 if successful, otherwise an operating system error code DESCRIPTION: This function locates the first file on the disk which matches the given pattern. The "mattrs" field specifies any special attributes the files must have in order to be matched, use 0 for normal directory searches. Subsequent files may be located using the "find_next" function. The above function prototype describes the MS-DOS implementation of the function. With other operating systems, the function may have slightly different parameters, due to differing information available. See your implementation notes. EXAMPLES: if(find_first(pattern, 0, name, &sh, &sl, &a, &t, &d)) abort("No matching files found\n"); FIND_NEXT FIND_NEXT PROTOTYPE: int find_next(char name[], int &sizeh, int &sizel, int &attrs, int &time, int &date) ARGUMENTS: name - Address of string to receive file name &sizeh - Address of int to receive high word of size &sizel - Address of int to receive low word of size &attrs - Address of int to receive attributes &time - Address of int to receive time stamp &date - Address of int to receive date stamp RETURN VALUE: 0 if successful, otherwise an operating system error code DESCRIPTION: The function must be preceeded by a call to "find_first", and will locate the next file on the disk which matches the pattern and attributes given to that function call. The above function prototype describes the MS-DOS implementation of the function. With other operating systems, the function may have slightly different parameters, due to differing information available. See your implementation notes. EXAMPLES: do printf("%s\n", name); while(!find_next(name, &sh, &sl, &a, &t, &d)); FOPEN FOPEN PROTOTYPE: FILE *fopen(char *filename, char *options) ARGUMENTS: filename- Name of the file to open options - String containing open options: 'a' - Append to file (must use with 'w') 'b' - Binary mode (default is text) 'q' - Quit { exit(-1) } on failure 'r' - Open file for read 'v' - Issue error message on failure 'w' - Open file for write RETURN VALUE: File pointer to the file buffer for the open file Zero (0) if file could not be opened DESCRIPTION: This function opens a file for buffered input ('r') or output ('w'), allowing subsequent I/O operations to read or write the file. If the 'b' option is NOT included, the file is assumed to be a TEXT file, and appropriate translations are made for NEWLINE and EOF interpretation. The size of the I/O buffer used is established by "fopen" from the external variable 'IOB_size', which has a default value of 256 (bytes). This variable is defined in the 'file.h' header file, and may be modified prior to calling this function if you wish to use a different buffer size. One I/O buffer is allocated from the heap for each open file. When using a large IOB_size value, you must be careful not to consume more memory than is available. EXAMPLES: fp = fopen("input_file", "r"); fp = fopen("input_file", "rvq"); IOB_size = 1024*10; /* Set up a 10K buffer */ fp = fopen("output_file", "wb"); FPRINTF FPRINTF PROTOTYPE: register fprintf(FILE *fp, char *format, arg, ...) ARGUMENTS: fp - File pointer to an output file format - Pointer to format string arg - Argument as determined by format string ... - Additional arguments may be required RETURN VALUE: None DESCRIPTION: This routine performs a formatted print to a file specified by 'fp'. The 'format' string is written to the file with the arguments substituted for special "conversion characters". These "conversion characters" are identified by a preceeding '%', and may be one of the following: b - Binary number c - Character d - Decimal (signed) number o - Octal number s - String u - Unsigned decimal number x - Hexidecimal number % - A single percent sign (No argument used) A numeric "field width" specifier may be placed in between the '%' and the conversion character, in which case the value will be output in a field of that width. If the "field width" is a negative number, the output will be left justified in the field, otherwise it is right justified. If the field width contains a leading '0', then the output field will be padded with zero's, otherwise spaces are used. If no "field width" is given, the output is free format, using only as much space as required. NOTE: This function uses a variable number of arguments, and must be declared as "register" (See "stdio.h"). EXAMPLES: fprintf(stderr,"Filename='%s'\n", filename); fprintf(stdout,"Address=%04x\n", address); fprintf(outfile,"Amount: $%3u.%02u\n", amount / 100, amount % 100); FPUTS FPUTS PROTOTYPE: fputs(char *string, FILE *fp) ARGUMENTS: string - Pointer to a character string fp - FIle pointer to output file RETURN VALUE: 0 if successful, otherwise an operating system error code DESCRIPTION: The "fputs" function writes the specified string to the indicated output file. The zero terminating the string is NOT written. EXAMPLES: fputs("Text message", output_file); FREAD FREAD PROTOTYPE: int fread(char *buffer, int size, FILE *fp) ARGUMENTS: buffer - Pointer to buffer to receive data size - Number of bytes to read fp - File pointer to an input file RETURN VALUE: Number of bytes read from file DESCRIPTION: This function reads a block of data from a file and places it in memory at the address of "buffer". Data will be read in either TEXT or BINARY form, depending on how the file was opened. If the number of bytes returned is less than the number of bytes requested, either the end of the file was encountered or an error condition occured (in which case the value will be zero). EXAMPLES: fread(block, 512, input_fp); FREE FREE PROTOTYPE: free(char *ptr) ARGUMENTS: ptr - Pointer to a previously allocated memory block RETURN VALUE: None DESCRIPTION: The "free" function releases (de-allocates) a block of memory that was obtained via a call to "malloc", and returns it to the heap. This makes it available for use by other memory allocations. EXAMPLES: if(!(ptr = malloc(BUFSIZ))) /* Allocate a temporary buffer */ abort("Not enough memory"); do { /* Copy the file over */ size = fread(ptr, BUFSIZ, in_fp); fwrite(ptr, size, out_fp); } while(size == BUFSIZ); free(ptr); /* Release temporary buffer */ FSCANF FSCANF PROTOTYPE: register int fscanf(FILE *fp, char *format, &arg, ...) ARGUMENTS: fp - File pointer to an input file format - Pointer to format string arg - Argument as determined by format string ... - Additional arguments may be required RETURN VALUE: The number of successful matches EOF (-1) if end of file or an error condition occurs DESCRIPTION: This routine reads a line from the specified file and scans it for specific values which are then assigned to the passed argument addresses. The types of values scanned are determined by special "conversion characters" within the "format" string. These "conversion characters" are identified by a preceeding '%', and may be one of the following: b - Binary number c - Character d - Decimal (signed) number o - Octal number s - String u - Unsigned decimal number x - Hexidecimal number % - A single percent sign (No argument used) Before scanning for any value, any leading "space" or "tab" characters in the input line are automatically flushed. Scanning of a particular value type will terminate when either the end of the line or a non-applicible character is encountered. Scanning of strings (%s) stops with a "space" or "tab" character, and the stored string will be zero terminated. A numeric "field width" specifier may be placed in between the '%' and the conversion character, in which case scanning of the value will also terminate if that many input characters have been processed. Scanning for characters (%c) assumes a "field width" of 1 character (%1c) unless it is otherwise specified. Any other (non-conversion) characters in the format string will cause the next character in the input string which is not a "space" or "tab" to be skipped if it matches that character. Any variable values from the input line which are not required must be cleared by scanning them into a "dummy" variable. The most common mistake when using "fscanf" is forgetting to use the '&' operator with a simple variable argument. This causes "fscanf" to store the value INDIRECTLY at the address contained in that variable (Similar to using '*' with a pointer) instead of storing the value into the actual variable itself. Arguments which are array names do not require the '&' operator, since the address of the array is already generated by reference to its name. Unlike "fscanf" in most other compiler libraries, the MICRO-C function always reads and scans a single line from the input file. NOTE: This function uses a variable number of arguments, and must be declared as "register". EXAMPLES: if(fscanf(infile,"%s %s %u", first_name, last_name, &age) != 3) abort("Error in user record\n"); FSEEK FSEEK PROTOTYPE: (1) int fseek(FILE *fp, int h_offset, unsigned l_offset, int mode) (2) int fseek(FILE *fp, int offset, mode) ARGUMENTS: fp - File pointer to an open file h_offset- Highest 16 bits of offset value l_offset- Lowest 16 bits of offset value offset - 16 bit offset value mode - Type of seek 0 = Absolute from start of file 1 = Signed offset from current position 2 = Signed offset from end of file RETURN VALUE: 0 if successful, otherwise an operating system error code DESCRIPTION: This function positions the operating system internal pointer into a file so that any read or write will take place at the specified position in the file. Most operating systems which support files of > 64K bytes in size will support form (1) of the function, using both high and low offset values. Smaller operating systems may only support form (2) of the function, allowing seeking of only +/- 32K bytes. Also, some implementations may not support all "modes", or may only allow unsigned (positive) offsets. EXAMPLES: fseek(in_file, 0, 2); /* Advance to end of file */ FTELL FTELL PROTOTYPE: (1) int ftell(FILE *fp, int &h_offset, unsigned &l_offset) (2) int ftell(FILE *fp, int &offset) ARGUMENTS: fp - File pointer to an open file h_offset- Address of int to receive high word of offset l_offset- Address of int to receive low word of offset offset - Address of int to receive offset RETURN VALUE: 0 if successful, otherwise an operating system error code DESCRIPTION: This function gets the current read/write position within a file. The position returned indicates the absolute character (byte) offset from the start of the file where the next read or write will take place. Most operating systems which support files of > 64K bytes in size will support form (1) of the function, returning both high and low offset values. Smaller operating systems may only support form (2) of the function, allowing access to only the first 65535 character positions. EXAMPLES: ftell(fp, &oldh, &oldl); /* Save file position */ . . . /* Perform some operations on the file */ fseek(fp, oldh, oldl, 0); /* Return to previous position */ FWRITE FWRITE PROTOTYPE: int fwrite(char *block, int size, FILE *fp) ARGUMENTS: block - Pointer to a block of data to write size - Number of bytes to write fp - File pointer to an output file RETURN VALUE: 0 if successful, otherwise an operating system error code DESCRIPTION: This function writes a block of data to the indicated file from memory at the specified address. Data is written in either TEXT or BINARY mode, depending on how the file was opened. If the value returned is less than the value of the "size" parameter, some error condition has occured (Such as disk full). EXAMPLES: if(fwrite(buffer, 100, fp) < 100) abort("File write error\n"); GETC GETC PROTOTYPE: int getc(FILE *fp) ARGUMENTS: fp - File pointer to an input file RETURN VALUE: Value of a character read from the file (0-255) EOF (-1) if end of file or an error condition occurs DESCRIPTION: This function reads a single character from an input file, and returns it as a positive value in the range of 0 to 255. A full 16 bit value is returned, allowing the end of file condition to be distinct from the character value 255. EXAMPLES: if((c = getc(input_file)) == EOF) abort("End of file encountered\n"); GETDIR GETDIR PROTOTYPE: int getdir(char pathname[]) ARGUMENTS: pathname- Address of string to receive directory path RETURN VALUE: 0 if successful, otherwise an operating system error code DESCRIPTION: This function retreives from the system the name of the "current" directory path. The "pathname" string must be long enough to hold the largest pathname supported by the system, as indicated by the "PATH_SIZE" definition in the "file.h" header file. EXAMPLES: getdir(¤t_dir); GETENV GETENV PROTOTYPE: int getenv(char *ename, char *dest) ARGUMENTS: ename - String containing name of environment variable dest - Buffer to receive variable string value RETURN VALUE: 1 if environment variable was found, 0 if not. DESCRIPTION: The GETENV function gets the value of a variable in the programs environment, and returns it as a string. If the environment variable is not found, zero is returned, and the destination buffer is set to a null (zero length) string. Use of this function allows a programs fixed parameters and options to be specified once in environment variables, which may then be extracted by the program, eliminating the need to specify those values every time the program is executed. When operating MICRO-C under operating systems which do not support environment variables, this function will not be available. EXAMPLES: if(!getenv("COMSPEC", command)) abort("No command processor defined\n"); IN IN PROTOTYPE: int in(unsigned port) ARGUMENTS: port - I/O port address RETURN VALUE: The 8 bit value read from the given I/O port address DESCRIPTION: The "in" function reads and returns a byte (8 bits) from an I/O port as an integer value between 0 and 255. The valid range of values for "port" depends on the I/O address space of the processor. This function is not provided for processors which do not support a separate I/O address space. EXAMPLES: while(in(0)); /* Wait for flag to clear */ INW INW PROTOTYPE: int inw(unsigned port) ARGUMENTS: port - I/O port address RETURN VALUE: The 16 bit value read from the given I/O port address DESCRIPTION: The "inw" function reads and returns a word (16 bits) from an I/O port as an integer value between 0 and 65535 (-1). The valid range of values for "port" depends on the I/O address space of the processor. This function is not provided for processors which do not support a separate I/O address space. EXAMPLES: var = inw(0); ISALNUM ISALNUM PROTOTYPE: int isalnum(char c) ARGUMENTS: c - Any character value RETURN VALUE: 1 if 'c' is alphabetic or numeric 0 if 'c' is not alphabetic or numeric DESCRIPTION: Returns TRUE (1) if the passed character 'c' is an ASCII alphabetic letter in either upper or lower case or if 'c' is a numeric digit, otherwise FALSE (0) is returned. EXAMPLES: while(isalnum(*ptr)) /* Copy over symbol name */ *name++ = *ptr++; ISALPHA ISALPHA PROTOTYPE: int isalpha(char c) ARGUMENTS: c - Any character value RETURN VALUE: 1 if 'c' is alphabetic 0 if 'c' is not alphabetic DESCRIPTION: Returns TRUE (1) if the passed character 'c' is an ASCII alphabetic letter in either upper or lower case, otherwise FALSE (0) is returned. EXAMPLES: flag = isalpha(input_char); ISCNTRL ISCNTRL PROTOTYPE: int iscntrl(char c) ARGUMENTS: c - Any character value RETURN VALUE: 1 if 'c' is a "control" character 0 if 'c' is not a "control" character DESCRIPTION: Returns TRUE (1) is the passed character 'c' is an ASCII "control" character (0x00-0x1F or 0x7F), otherwise FALSE (0) is returned. EXAMPLES: putc(iscntrl(c) ? '.' : c, stdout); /* Display controls as '.' */ ISDIGIT ISDIGIT PROTOTYPE: int isdigit(char c) ARGUMENTS: c - Any character value RETURN VALUE: 1 if 'c' is numeric 0 if 'c' is not numeric DESCRIPTION: Returns TRUE (1) is the passed character 'c' is an ASCII digit ('0'-'9'), otherwise FALSE (0) is returned. EXAMPLES: value = 0; while(isdigit(*ptr)) value = (value * 10) + (*ptr++ - '0'); ISGRAPH ISGRAPH PROTOTYPE: int isgraph(char c) ARGUMENTS: c - Any character value RETURN VALUE: 1 if 'c' is a non-space printable character 0 if 'c' is a space or not printable DESCRIPTION: Returns TRUE (1) if the passed character 'c' is a printable ASCII character other than a space character, otherwise FALSE (0) is returned. EXAMPLES: putc(isgraph(c) ? c : '.', stdout); ISLOWER ISLOWER PROTOTYPE: int islower(char c) ARGUMENTS: c - Any character value RETURN VALUE: 1 if 'c' is lower case alphabetic 0 if 'c' is not lower case alphabetic DESCRIPTION: Returns TRUE (1) if the passed character 'c' is an ASCII alphabetic letter of lower case, otherwise FALSE (0) is returned. EXAMPLES: flag = islower(input_char); ISPUNCT ISPUNCT PROTOTYPE: int ispunct(char c) ARGUMENTS: c - Any character value RETURN VALUE: 1 if 'c' is a printable non-alphanumeric character 0 if 'c' is not printable or alphanumeric DESCRIPTION: Returns TRUE (1) if the passed character 'c' is a printable ASCII character which is not a letter of the alphabet or a numeric digit, otherwise FALSE (0) is returned. EXAMPLES: while(ispunct(*ptr)) ++ptr; ISSPACE ISSPACE PROTOTYPE: int isspace(char c) ARGUMENTS: c - Any character value RETURN VALUE: 1 if 'c' is a space character (space, tab or newline) 0 if 'c' is not a space character DESCRIPTION: Returns TRUE (1) if the passed character 'c' is one of a space, tab or newline, otherwise FALSE (0) is returned. EXAMPLES: while(isspace(*ptr)) ++ptr; ISUPPER ISUPPER PROTOTYPE: int isupper(char c) ARGUMENTS: c - Any character value RETURN VALUE: 1 if 'c' is upper case alphabetic 0 if 'c' is not upper case alphabetic DESCRIPTION: Returns TRUE (1) if the passed character 'c' is an ASCII alphabetic letter of upper case, otherwise FALSE (0) is returned. EXAMPLES: flag = isupper(input_char); LGETC LGETC PROTOTYPE: int lgetc(HANDLE fh) ARGUMENTS: fh - File handle for an input file RETURN VALUE: Value of a character read from the file (0-255) EOF (-1) if end of file or an error condition occurs DESCRIPTION: This function reads a single character from an input file using LOW LEVEL (unbuffered) I/O, and returns it as a positive value in the range of 0 to 255. A full 16 bit value is returned, allowing the end of file condition to be distinct from the character value 255. EXAMPLES: if((c = lgetc(input_file)) == EOF) abort("End of file encountered\n"); LGETS LGETS PROTOTYPE: char *lgets(char *buffer, int size, HANDLE fh) ARGUMENTS: buffer - Pointer to string to receive line size - Maximum size of line to read fh - File handle of an input file RETURN VALUE: Pointer to "buffer", or 0 if end of file DESCRIPTION: The "lgets" function reads characters from the specified input file using LOW LEVEL (unbuffered) I/O, and places them in the character buffer until one of three things happens: 1) A NEWLINE character is encountered. 2) The END of the file is encountered. 3) The limit of "size" characters are read. The string is terminated with the standard NULL (00) character. The trailing NEWLINE '\n' character is NOT included in the output buffer. EXAMPLES: lgets(input_line, 80, L_stdin); LPUTC LPUTC PROTOTYPE: lputc(char c, HANDLE fh) ARGUMENTS: c - Any character value fh - File handle of an output file RETURN VALUE: 0 if successful, otherwise an operating system error code DECRIPTION: This function writes the character 'c' to the file indicated by 'fh'. The "newline" (\n) character will be translated into whatever character(s) are required by the operating system to separate records in the file. EXAMPLES: lputc('*', fh); lputc('\n', L_stderr); LPUTS LPUTS PROTOTYPE: lputs(char *string, HANDLE fh) ARGUMENTS: string - Pointer to a character string fh - File handle of an output file RETURN VALUE: 0 if successful, otherwise an operating system error code DESCRIPTION: The "lputs" function writes the specified string to the indicated output file using LOW LEVEL (unbuffered) I/O. The zero terminating the string is NOT written. EXAMPLES: lputs("Text message", output_fh); LONGJMP LONGJMP PROTOTYPE: longjmp(int savenv[3], int rvalue) ARGUMENTS: savenv - Save area for program context rvalue - Value to be returned by "setjmp" RETURN VALUE: N/A - Function never returns DESCRIPTION: The "longjmp" function causes execution to transfer to the "setjmp" call which set up the "savenv" variable. The "setjmp" function will appear to return the value of "rvalue". NOTE-1: "longjmp" may only be used from within the function calling "setjmp" or a function which has been called "beneath" that function. IT MUST NOT BE USED AFTER THE FUNCTION CALLING "SETJMP" HAS TERMINATED. NOTE-2: If "rvalue" is zero, the function calling "setjmp" will assume that it is returning from initialization. Unless you want this unusual behavior, you should not pass a return value of zero to "longjmp". See also SETJMP. EXAMPLES: if(getc(stdin) == ('C'-'@')) /* If Control-C entered... */ longjmp(savearea, 1); /* Return to main function */ LREWIND LREWIND PROTOTYPE: int lrewind(HANDLE fh) ARGUMENTS: fh - File handle of an open file RETURN VALUE: 0 if successful, otherwise an operating system error code DESCRIPTION: This function resets the operating system internal file handle so than any subsequent read or writes will be at the beginning of the file. For use with LOW LEVEL (unbuffered) file I/O only. EXAMPLES: lrewind(input_fh); LSEEK LSEEK PROTOTYPE: (1) int lseek(HANDLE fh, int h_offset, unsigned l_offset, int mode) (2) int lseek(HANDLE fh, int offset, mode) ARGUMENTS: fh - File handle of an open file h_offset- Highest 16 bits of offset value l_offset- Lowest 16 bits of offset value offset - 16 bit offset value mode - Type of seek 0 = Absolute from start of file 1 = Signed offset from current position 2 = Signed offset from end of file RETURN VALUE: 0 if successful, otherwise an operating system error code DESCRIPTION: This function positions the operating system internal pointer into a file so that any read or write will take place at the specified position in the file. Most operating systems which support files of > 64K bytes in size will support form (1) of the function, using both high and low offset values. Smaller operating systems may only support form (2) of the function, allowing seeking of only +/- 32K bytes. Also, some implementations may not support all "modes", or may only allow unsigned (positive) offsets. For use with LOW LEVEL (unbuffered I/O only). EXAMPLES: lseek(input_fh, 0, 2); /* Advance to end of file */ LTELL LTELL PROTOTYPE: (1) int ltell(HANDLE fh, int &h_offset, unsigned &l_offset) (2) int ltell(HANDLE fh, int &offset) ARGUMENTS: fh - File handle of an open file h_offset- Address of int to receive high word of offset l_offset- Address of int to receive low word of offset offset - Address of int to receive offset RETURN VALUE: 0 if successful, otherwise an operating system error code DESCRIPTION: This function gets the current read/write position within a file. The position returned indicates the absolute character (byte) offset from the start of the file where the next read or write will take place. Most operating systems which support files of > 64K bytes in size will support form (1) of the function, returning both high and low offset values. Smaller operating systems may only support form (2) of the function, allowing access to only the first 65535 character positions. For use with LOW LEVEL (unbuffered I/O only). EXAMPLES: ltell(fp, &oldh, &oldl); /* Save file position */ . . . /* Perform some operations on the file */ lseek(fp, oldh, oldl, 0); /* Return to previous position */ MALLOC MALLOC PROTOTYPE: char *malloc(int size) ARGUMENTS: size - Size of memory block to allocate (in bytes). RETURN VALUE: 0 - Memory allocation failed !0 - Pointer to allocated memory block DESCRIPTION: The "malloc" function allocates a block of memory of the specified size from the heap, and returns a pointer to it. This memory will remain allocated until it is explicitly releases with the "free" function. EXAMPLES: if(!(ptr = malloc(BUFSIZ))) /* Allocate a temporary buffer */ abort("Not enough memory"); do { /* Copy the file over */ size = fread(ptr, BUFSIZ, in_fp); fwrite(ptr, size, out_fp); } while(size == BUFSIZ); free(ptr); /* Release temporary buffer */ MAX MAX PROTOTYPE: int max(int value1, int value2) ARGUMENTS: value1 - Any integer value value2 - Any integer value RETURN VALUE: The greater of "value1" or "value2" DESCRIPTION: The "max" function returns the higher of its two argument values. EXAMPLES: biggest = max(a, b); MEMCPY MEMCPY PROTOTYPE: memcpy(char *dest, char *source, unsigned size) ARGUMENTS: dest - Pointer to the destination source - Pointer to the souce size - Number of bytes to copy RETURN VALUE: None DESCRIPTION: The "memcpy" function will copy the specified number of bytes from the source to the destination. EXAMPLES: memcpy(buffer1, buffer2, 256); MEMSET MEMSET PROTOTYPE: memset(char *block, char value, unsigned size) ARGUMENTS: block - Pointer to a block of memory value - Value to initialize memory with size - Number of bytes to initialize RETURN VALUE: None DESCRIPTION: Sets a block of memory beginning at the pointer "block", for "size" bytes to the byte value "value". EXAMPLES: memset(buffer, 0, 100); MIN MIN PROTOTYPE: int min(int value1, int value2) ARGUMENTS: value1 - Any integer value value2 - Any integer value RETURN VALUE: The smaller of "value1" or "value2" DESCRIPTION: The "min" function returns the lower of its two argument values. EXAMPLES: least = min(a, b); MKDIR MKDIR PROTOTYPE: int mkdir(char *pathname) ARGUMENTS: pathname- Name of directory to create RETURN VALUE: 0 if successful, otherwise an operating system error code DESCRIPTION: The "mkdir" function create a new directory on the disk under the specified path name. EXAMPLES: mkdir("subdir"); NARGS NARGS PROTOTYPE: int nargs() ARGUMENTS: None RETURN VALUE: The number of arguments passed to the calling function DESCRIPTION: Returns the number of arguments passed to a "register" function. NOTE: When calling a "register" function, MICRO-C loads the accumulator with the number of arguments just prior to calling the function. This "nargs" routine is simply a null definition which returns with the same value in the accumulator as was there when it was called. Therefore "nargs" MUST BE THE FIRST ARITHMETIC ENTITY EVALUATED WITHIN THE REGISTER FUNCTION or the contents of the accumulator will be lost. Some examples of "register" definitions and the use of "nargs" may be found in the library source code. EXAMPLES: first_arg = nargs() * 2 + &arguments; OPEN OPEN PROTOTYPE: HANDLE open(char *filename, int options) ARGUMENTS: filename- Name of the file to open options - Open options (defined in file.h) RETURN VALUE: File handle for the open file Zero (0) if file could not be opened DESCRIPTION: This function open a file for direct access via LOW LEVEL (unbuffered) I/O. EXAMPLES: if(fh = open("data.img", F_READ)) { read(data_buf, 100, fh); close(fh); } else abort("Unable to read data file"); OUT OUT PROTOTYPE: out(unsigned port, int value) ARGUMENTS: port - I/O port address value - Value to write to I/O port RETURN VALUE: None DESCRIPTION: The "out" function writes a byte (8 bit) value to an I/O port. The valid range of values for "port" depends on the I/O address space of the processor. This function is not provided for processors which do not support a separate I/O address space. EXAMPLES: out(0, 0); /* Output 0 to I/O port 0 */ OUTW OUTW PROTOTYPE: outw(unsigned port, int value) ARGUMENTS: port - I/O port address value - Value to write to I/O port RETURN VALUE: None DESCRIPTION: The "outw" function writes a word (16 bit) value to an I/O port. The valid range of values for "port" depends on the I/O address space of the processor. This function is not provided for processors which do not support a separate I/O address space. EXAMPLES: outw(0, 0); /* Write 0 to I/O ports 0 and 1 */ PEEK PEEK PROTOTYPE: (1) int peek(unsigned address) (2) int peek(unsigned h_addr, unsigned l_addr) (3) int peek(unsigned segment, unsigned offset) ARGUMENTS: segment - Memory segment offset - Offset into segment h_addr - High word of memory address l_addr - Low word of memory address address - 16 bit memory address RETURN VALUE: The 8 bit value read from the given memory address DESCRIPTION: The "peek" function reads and returns a byte (8 bits) from memory as an integer value between 0 and 255. Processors such as the 8080 or 6809 which address 64K of memory or less use form (1) of the function. Non-segmented processors addressing more than 64K such as the 68000 use form (2) of the function. Processors employing a "segmented" architecture such as the 8086 use form (3) of the function. EXAMPLES: while(peek(0)); /* Wait for flag to clear */ PEEKW PEEKW PROTOTYPE: (1) int peekw(unsigned address) (2) int peekw(unsigned h_addr, unsigned l_addr) (3) int peekw(unsigned segment, unsigned offset) ARGUMENTS: segment - Memory segment offset - Offset into segment h_addr - High word of memory address l_addr - Low word of memory address address - 16 bit memory address RETURN VALUE: The 16 bit value read from the given memory address DESCRIPTION: The "peekw" function reads and returns a word (16 bits) from memory as an integer value between 0 and 65535 (-1). Processors such as the 8080 or 6809 which address 64K of memory or less use form (1) of the function. Non-segmented processors addressing more than 64K such as the 68000 use form (2) of the function. Processors employing a "segmented" architecture such as the 8086 use form (3) of the function. EXAMPLES: var = peekw(0)); POKE POKE PROTOTYPE: (1) poke(unsigned address, int value) (2) poke(unsigned h_addr, unsigned l_addr, int value) (3) poke(unsigned segment, unsigned offset, int value) ARGUMENTS: segment - Memory segment offset - Offset into segment h_addr - High word of memory address l_addr - Low word of memory address address - 16 bit memory address value - Value to be written to memory RETURN VALUE: None DESCRIPTION: The "poke" function writes a byte (8 bit) value to memory. Processors such as the 8080 or 6809 which address 64K of memory or less use form (1) of the function. Non-segmented processors addressing more than 64K such as the 68000 use form (2) of the function. Processors employing a "segmented" architecture such as the 8086 use form (3) of the function. EXAMPLES: poke(0, 0); /* Write 0 to location 0 */ POKEW POKEW PROTOTYPE: (1) pokew(unsigned address, int value) (2) pokew(unsigned h_addr, unsigned l_addr, int value) (3) pokew(unsigned segment, unsigned offset, int value) ARGUMENTS: segment - Memory segment offset - Offset into segment h_addr - High word of memory address l_addr - Low word of memory address address - 16 bit memory address value - Value to be written to memory RETURN VALUE: None DESCRIPTION: The "pokew" function writes a word (16 bit) value to memory. Processors such as the 8080 or 6809 which address 64K of memory or less use form (1) of the function. Non-segmented processors addressing more than 64K such as the 68000 use form (2) of the function. Processors employing a "segmented" architecture such as the 8086 use form (3) of the function. EXAMPLES: pokew(0, 0); /* Write 0 to locations 0 and 1 */ PRINTF PRINTF PROTOTYPE: register printf(char *format, arg, ...) ARGUMENTS: format - Pointer to format string arg - Argument as determined by format string ... - Additional arguments may be required RETURN VALUE: None DESCRIPTION: The "printf" routine performs a formatted print to the standard output device (usually system console). The "format" string is written with the arguments substituted for special "conversion characters". See "fprintf" for more information on format strings. NOTE: This function uses a variable number of arguments, and must be declared as "register" (See "stdio.h"). EXAMPLES: printf("Hello world!!!\n"); printf("File '%s', has %u lines\n", filename, num_lines); PUTC PUTC PROTOTYPE: putc(char c, FILE *fp) ARGUMENTS: c - Any character value fp - File pointer to an output file RETURN VALUE: 0 if successful, otherwise an operating system error code DECRIPTION: This function writes the character 'c' to the file indicated by the file pointer 'fp'. EXAMPLES: putc('*', fp); putc('\n', stderr); RAND RAND PROTOTYPE: unsigned rand(unsigned limit) ARGUMENTS: limit - Maximum value to return RETURN VALUE: A pseudo-random number in the range of 0 to (limit-1) DESCRIPTION: The "rand" function calculates the next value of a pseudo-random sequence, based on a 16 bit unsigned "seed" value, which it maintains in the global variable "RAND_SEED". The new value is stored as the new seed value, and is then divided by the "limit" parameter, to obtain the remainder, which is returned. This results in a random number in the range of zero (0) to (limit - 1). Any particular sequence may be repeated, by reseting the "RAND_SEED" value. EXAMPLES: value = rand(52); READ READ PROTOTYPE: int read(char *buffer, int size, HANDLE fh) ARGUMENTS: buffer - Pointer to buffer to receive data size - Number of bytes to read fh - File handle of an input file RETURN VALUE: Number of bytes read from file DESCRIPTION: This function reads a block of data from a file using LOW LEVEL (unbuffered) I/O, and places it in memory at the address of "buffer". Data is read in "raw" form, with no interpretation of "newline" characters etc. If the number of bytes returned is less than the number of bytes requested, either the end of the file was encountered or an error condition occured (in which case the value will be zero). EXAMPLES: read(block, 512, input_fh); RENAME RENAME PROTOTYPE: int rename(char *pathname, char *newname) ARGUMENTS: pathname- Name of file to rename newname - New name for file RETURN VALUE: 0 if successful, otherwise an operating system error code DESCRIPTION: This function changes the name of an existing file to the ASCII string specified by newname. EXAMPLES: rename("output.dat", "output.bak"); REWIND REWIND PROTOTYPE: int rewind(FILE *fp) ARGUMENTS: fp - File pointer to an open file RETURN VALUE: 0 if successful, otherwise an operating system error code DESCRIPTION: This function resets the operating system internal file pointer so than any subsequent read or writes will be at the beginning of the file. EXAMPLES: rewind(input_file); RMDIR RMDIR PROTOTYPE: int rmdir(char *pathname) ARGUMENTS: pathname- Name of directory to delete RETURN VALUE: 0 if successful, otherwise an operating system error code DESCRIPTION: This function removes a directory from the disk. On most systems, the directory must be empty (contains no files) otherwise the function will fail. EXAMPLES: rmdir("subdir"); SCANF SCANF PROTOTYPE: register int scanf(char *format, arg1, arg2, ...) ARGUMENTS: format - Pointer to format string arg - Argument as determined by format string ... - Additional arguments may be required RETURN VALUE: The number of successful matches EOF (-1) if end of file or an error condition occurs DESCRIPTION: The "scanf" function reads and scans a line from the standard input device (usually system console) for specific values. Values are read and assigned to the passed argument addresses according to special "conversion characters" in the "format" string. See "fscanf" for more information on format strings. NOTE: This function uses a variable number of arguments, and must be declared as "register". EXAMPLES: do printf("Please enter your First & Last names, and your age?"); while(scanf("%s %s %u", first_name, last_name, &age) != 3); SETBUF SETBUF PROTOTYPE: FILE *setbuf(FILE *fp, int size) ARGUMENTS: fp - File pointer to an open file size - Size of new I/O buffer RETURN VALUE: If successful, a new file pointer is returned, and the old one is released. On failure the old file pointer is returned. DESCRIPTION: The "setbuf" function will adjust the size of the buffer used for I/O operations on the indicated open file. This is the ONLY way to set the buffer size for the "stdin" and "stdout" streams. If you change the size of the "stdout" buffer, you must remember to "fflush(stdout)" before terminating, otherwise the last buffer contents may not be written. For file opened by "fopen", the buffer size may be set more efficently by setting the value of the external variable "IOB_size" prior to calling "fopen". If "setbuf" is unable to allocate space for the new buffer, it will return the old file pointer unchanged. EXAMPLES: stdout = setbuf(stdout, 512); /* Set stdout to 512 byte buffer */ SETJMP SETJMP PROTOTYPE: int setjmp(int savenv[3]) ARGUMENTS: savenv - Save area for program context RETURN VALUE: 0 is returned when actually called Value passed to "longjmp" is returned otherwise DESCRIPTION: When called, the "setjmp" function stores the current execution state of the program into the passed integer array, and returns the value zero. The "longjmp" function may then be used to return the program to the "setjmp" call. In this case, the value returned by "setjmp" will be the value which was passed to "longjmp". This allows the function containing "setjmp" to determine which call to "longjmp" transfered execution to it. See also LONGJMP. EXAMPLES: switch(setjmp(savearea)) { case 0 : printf("Longjmp has been set up"); break; case 1 : printf("Control-C Interrupt"); break; case 2 : printf("Reset command executed"); break; default: printf("Software error trap"); break; } SPRINTF SPRINTF PROTOTYPE: register sprintf(char *dest, char *format, arg, ...) ARGUMENTS: dest - Pointer to destination string format - Pointer to format string arg - Argument as determined by format string ... - Additional arguments may be required RETURN VALUE: None DESCRIPTION: The "sprintf" routine performs a formatted print to a string in memory. The "format" string is written to the destination string with the arguments substituted for special "conversion characters". See "fprintf" for more information on format strings. NOTE: This function uses a variable number of arguments, and must be declared as "register" (See "stdio.h"). EXAMPLES: sprintf(header_file, "/lib/%s.h", header_name); SQRT SQRT PROTOTYPE: int sqrt(unsigned value) ARGUMENTS: value - Number for which to calculate square root RETURN VALUE: The integer square root (rounded up) of the argument value DESCRIPTION: The SQRT function returns the smallest number which when multiplied by itself will give a number equal to or larger that the argument value. EXAMPLES: /* * Draw a circle about point (x, y) of radus (r) */ circle(x, y, r) int x, y, r; { int i, j, k, rs, lj; rs = (lj = r)*r; for(i=0; i <= r; ++i) { j = k = sqrt(rs - (i*i)); do { plot_xy(x+i, y+j); plot_xy(x+i, y-j); plot_xy(x-i, y+j); plot_xy(x-i, y-j); } while(++j < lj); lj = k; } } SSCANF SSCANF PROTOTYPE: register int sscanf(char *input, char *format, arg1, arg2, ...) ARGUMENTS: input - Pointer to input string format - Pointer to format string arg - Argument as determined by format string ... - Additional arguments may be required RETURN VALUE: The number of successful matches DESCRIPTION: The "sscanf" function scans a string in memory for specific values. Values are read and assigned to the passed argument addresses according to special "conversion characters" in the "format" string. See "fscanf" for more information on format strings. NOTE: This function uses a variable number of arguments, and must be declared as "register". EXAMPLES: sscanf(pathname,"/%s/%s", directory, filename); STRBEG STRBEG PROTOTYPE: int strbeg(char *string1, char *string2) ARGUMENTS: string1 - Pointer to character string to test string2 - Pointer to character string to check for RETURN VALUE: 0 - String1 does not begin with string2 1 - String1 begins with string2 DECRIPTION: Tests the passed "string1" to determine if it begins with the same data as is contained within "string2". EXAMPLES: if(strbeg(command, "delete")) delete_file(&command[6]); STRCAT STRCAT PROTOTYPE: char *strcat(char *dest, *source) ARGUMENTS: dest - Pointer to destination string source - Pointer to source string RETURN VALUE: Pointer to zero terminating destination string DESCRIPTION: This function concatinates the source string onto the tail of the destination string. The destination string must be large enough to hold the entire contents of both strings. EXAMPLES: strcat(program_name, ".c"); STRCHR STRCHR PROTOTYPE: char *strchr(char *string, char chr) ARGUMENTS: string - Pointer to a character string chr - Character to look for RETURN VALUE: Pointer to the first occurance of 'chr' in 'string' Zero (0) if character was not found DECRIPTION: Searches the passed string got the first occurance of the specified character. If the character is found, a pointer to its position in the string is returned. If the character is not found, a null pointer is returned. The null (0) character is treated as valid data by this function, thus: strchr(string, 0); would return the position of the null terminator of the string. EXAMPLES: comma = strchr(buffer, ','); STRCMP STRCMP PROTOTYPE: int strcmp(char *string1, char *string2) ARGUMENTS: string1 - Pointer to first string string2 - Pointer to second string RETURN VALUE: 0 - Strings match exactly 1 - String1 is greater than string2 -1 - String2 is greater than string1 DESCRIPTION: This function compares two strings character by character. If the two strings are identical, a zero (0) is returned. If the first string is greater than the second (as far as ASCII is concerned), a one (1) is returned. If the second string is greater, a negative one (-1) is returned. EXAMPLES: if(!strcmp(command, "quit")) exit(0); STRCPY STRCPY PROTOTYPE: char *strcpy(char *dest, char *source) ARGUMENTS: dest - Pointer to destination string souce - Pointer to source string RETURN VALUE: Pointer to zero terminating destination string DESCRIPTION: This function copies the source string to the destination string. All data is copied up to and including the zero byte which terminates the string. The destination string must be large enough to hold the entire source. EXAMPLES: strcpy(filename, argv[1]); STRLEN STRLEN PROTOTYPE: int strlen(char *string) ARGUMENTS: string - Pointer to a character string RETURN VALUE: The length of the string DECRIPTION: Returns the length in character of the passed string. The length does not include the zero byte which terminates the string. EXAMPLES: length = strlen(command); STRNCAT STRNCAT PROTOTYPE: char *strncat(char *dest, *source, unsigned length) ARGUMENTS: dest - Pointer to destination string source - Pointer to source string length - Maximum number of characters to copy RETURN VALUE: Pointer to zero terminating destination string DESCRIPTION: This function concatinates the source string onto the tail of the destination string. If the source string exceeds "length" bytes in size, only that many characters are copied. EXAMPLES: strncat(path, filename, 64); STRNCMP STRNCMP PROTOTYPE: int strncmp(char *string1, char *string2, unsigned length) ARGUMENTS: string1 - Pointer to first string string2 - Pointer to second string length - Number of bytes to compare RETURN VALUE: 0 - Strings match exactly 1 - String1 is greater than string2 -1 - String2 is greater than string1 DESCRIPTION: This function compares two strings character by character until either a difference is detected, or "length" characters have been compared. If the two string portions are identical, a zero (0) is returned. If the first string is greater than the second (as far as ASCII is concerned), a one (1) is returned. If the second string is greater, a negative one (-1) is returned. EXAMPLES: len = strlen(buffer) - 3; for(i=1; i < len; ++i) if(strncmp(&buffer[i], "***", 3) abort("Found three stars\n"); STRNCPY STRNCPY PROTOTYPE: strncpy(char *dest, char *source, unsigned length) ARGUMENTS: dest - Pointer to destination string souce - Pointer to source string length - Number of bytes to copy RETURN VALUE: None DESCRIPTION: This function copies "length" characters from the source string to the destination string. If the source string is shorter than "length", the destination string is padded with nulls. If the source string is longer than "length", only that many characters are copied, and the destination string is NOT zero terminated. EXAMPLES: strncpy(filename, argv[1], 64); STRSTR STRSTR PROTOTYPE: char *strstr(char *string1, char *string2) ARGUMENTS: string1 - Pointer to character string to test string2 - Pointer to substring to search for RETURN VALUE: Pointer to substring, or 0 if not found DECRIPTION: Searches the passed "string1" for the first occurance of the passed "string2". If found, a pointer to the beginning of that substring within "string1" is returned. EXAMPLES: if(ptr = strstr(command, "delete")) delete_file(&ptr[6]); SYSTEM SYSTEM PROTOTYPE: int system(char *command) ARGUMENTS: command - A system command to be executed RETURN VALUE: 0 if successful, otherwise an operating system error code DESCRIPTION: The SYSTEM function accepts any operating system command as a string parameter, and passes that command to the operating system to be executed. When the command has terminated, execution will resume in the MICRO-C program, with the statement following the call to SYSTEM. EXAMPLES: system("DEL *.TMP"); TOLOWER TOLOWER PROTOTYPE: char tolower(char c) ARGUMENTS: c - Any character value RETURN VALUE: The value of 'c', converted to lower case DESCRIPTION: Returns the value of 'c' converted to lower case. If 'c' is not a letter of upper case, no change is made, and the original value of 'c' is returned. EXAMPLES: input_char = tolower(getc(stdin)); TOUPPER TOUPPER PROTOTYPE: char toupper(char c) ARGUMENTS: c - Any character value RETURN VALUE: The value of 'c', converted to upper case DESCRIPTION: Returns the value of 'c' converted to upper case. If 'c' is not a letter of lower case, no change is made, and the original value of 'c' is returned. EXAMPLES: putc(toupper(output_char), stdout); WRITE WRITE PROTOTYPE: int write(char *block, int size, HANDLE fh) ARGUMENTS: block - Pointer to a block of data to write size - Number of bytes to write fh - File handle of an output file RETURN VALUE: 0 if successful, otherwise an operating system error code DESCRIPTION: This function writes a block of data to the indicated file using low level (unbuffered) I/O from memory at the specified address. Data is written in "raw" form, with no translations of "newline" characters etc. If the value returned is less than the value of the "size" parameter, some error condition has occured (Such as disk full). EXAMPLES: if(write(buffer, 100, fh) < 100) abort("File write error\n"); MICRO-C Library Page: 3 +---------------------------------+ | | | ***************************** | | * The IBM-PC/MS-DOS library * | | ***************************** | | | +---------------------------------+ 1.2 IBM-PC/MS-DOS Library The library functions described on the following pages are available only under the MS-DOS operating system, on IBM-PC or compatible systems. These routines perform operations which are closely tied to the 8086 family of processors, the IBM-PC hardware, or the MS-DOS operating system, and are therefore impractical to implement on a "general" basis. ALLOCA ALLOCA PROTOTYPE: char *alloca(int size) ARGUMENTS: size - Size of memory block to allocate (in bytes). RETURN VALUE: 0 - Memory allocation failed !0 - Pointer to allocated memory DESCRIPTION: The "alloca" function allocates a block of automatic (stack) memory, which exists only only until the function calling "alloca" returns. When that function returns, all stack memory including any allocated by "alloca" is released. NOTE: THE FOLLOWING RESTRICTIONS APPLY TO THE USE OF ALLOCA: The function calling 'alloca' MUST have at least one automatic (local) variable, otherwise MICRO-C will not restore the stack on exit. The 'alloca' function must be used within a simple expression, at a point where there will be no partial results stored on the stack. The above conditions can best be met by declaring a local pointer which will hold the memory address, and assigning it the value of the 'alloca' call in a single statement. The address returned by 'alloca' should NOT be assigned to a calculated address (such as an array element or indirect reference via a pointer), since this may result in stack activity. NOTE: The size operand to 'alloca' can be a complex expression, since any stack operations it causes will have dissipated by the time 'alloca' gets called. EXAMPLES: func(string) char *string; { char *local_memory; if(!(local_memory = alloca(strlen(string)+1))) abort("Not enough memory for alloca"); /* ... */ } ALLOC_SEG ALLOC_SEG PROTOTYPE: int alloc_seg(int size) ARGUMENTS: size - Number of 16 byte paragraphs to allocate RETURN VALUE: 0 - Not enough free memory available !0 - The segment address of the allocated memory DESCRIPTION: The "alloc_seg" function allocates a 'segment' of memory from DOS. The size is given in 16 byte "paragraphs". The allocated memory will be outside of the data memory available to the MICRO-C program, and therefore must be accessed via assembly lenguage functions, or with the "peek" and "poke" library functions. EXAMPLES: if(!(aseg = alloc(4096))) /* Get a 64K data segment */ abort("Not enough memory!!!"); set_es(aseg); /* Set up extra segment */ asm_func(); /* Invoke assembler function */ CCLOSE CCLOSE PROTOTYPE: Cclose() ARGUMENTS: None RETURN VALUE: None DESCRIPTION: This function closes the communications port previously opened using "Copen". The system interrupt vectors and all other hooks to the comm port are restored. This function must be called before any program using "Copen" terminates, otherwise the communications port will be left in an indeterminate state. If this is not done, there will be a possibility of system crash if an interrupt is received from the port after the program has terminated. EXAMPLES: Cclose(); /* Close comm port */ exit(0); /* And terminate */ CGETC CGETC PROTOTYPE: int Cgetc() ARGUMENTS: None RETURN VALUE: Character read from the communications port DESCRIPTION: This function reads a single character from the communications port previously opened with "Copen". If no character is available, "Cgetc" will wait for one. EXAMPLES: /* Get a string from the comm port */ while((c = cgetc()) != '\r') *ptr++ = c; *ptr = 0; COPEN COPEN PROTOTYPE: int Copen(int port, int speed, int mode, int modem) ARGUMENTS: port - Comm port to use (1 or 2) speed - Baudrate divisor to set mode - Communications parameters to set modem - Modem control lines to set RETURN VALUE: 0 - Successful open !0 - Requested comm port is not available DESCRIPTION: The "Copen" function opens a serial communications port on the IBM PC for access. An independant interrupt handler and I/O drivers are installed, which allow high speed full duplex operation of the serial port with optional XON/XOFF flow control of both receive and transmit streams. Only one serial port may be accessed at a time using these functions, If "Copen" is called more than once, it will automatically close the last port before opening the new one. The meaning of the "speed", "mode", and "modem" parameters if documented in the "comm.h" header file. An external "char" variable "Cflags" may be accessed to enable or disable transparency of the serial channel. When "transparent" is selected, XON/XOFF flow control is disabled, and all data is sent and received with no changes. When operating in this mode, you must insure that "Cgetc" is called frequently enough that the 256 byte internal receive buffer will not overflow. Since "Cflags" is used by the interrupt handler, you should disable and enable interrupts around any accesses to it. EXAMPLES: #include comm.h /* Get comm port defintions */ extern char Cflags; /* * Program to read & echo characters on the serial port * in transparent mode. (Until ESCAPE char is received) */ main() { char c; if(Copen(1, _2400, PAR_NO|DATA_8|STOP_1, SET_RTS|SET_DTR)) abort("Cannot access COM1"); disable(); /* Disable interrupts */ Cflags |= TRANSPARENT; /* Set transparency */ enable(); /* Re-enable interrupts */ while((c = Cgetc()) != 0x1B) /* Do until ESCAPE */ Cputc(c); Cclose(); /* Close the serial port */ } COPY_SEG COPY_SEG PROTOTYPE: copy_seg(int dseg, int doffset, int sseg, int soffset, int size) ARGUMENTS: dseg - Destination segment doffset - Destination offset sseg - Source segment soffset - Source offset size - Number of bytes to copy RETURN VALUE: None DESCRIPTION: This function perform a copy between 80X86 processor memory segments. A number of bytes equal to "size" is copied from the source segment and offset to the destination segment and offset. EXAMPLES: /* Save the video display contents */ copy_seg(get_ds(), buffer, _V_BASE, 0, (25*80)*2); CPU CPU PROTOTYPE: int cpu() ARGUMENTS: None RETURN VALUE: 0 - CPU is 8088 or 8086 1 - CPU is 80188 or 80186 2 - CPU is 80286 3 - CPU is 80386 or 80486 DESCRIPTION: This function returns a simple integer which identifies the processor type on which the program is currently executing. EXAMPLES: if(cpu() < 2) abort("This program requires at least an 80286"); CPUTC CPUTC PROTOTYPE: Cputc(char c) ARGUMENTS: c - Character to write to communciation port RETURN VALUE: None DESCRIPTION: The "Cputc" function writes the given character to the communcinations port previously opened by "Copen". EXAMPLES: while(*ptr) /* Write a string to comm port */ Cputc(*ptr++); CSIGNALS CSIGNALS PROTOTYPE: int Csignals() ARGUMENTS: None RETURN VALUE: The modem input signals read from the open comm port DESCRIPTION: This function reads the modem input signals (DSR, CD, RI etc) from the serial communication port previously opened by "Copen", and returns them as an integer value. The meaning of the individual bits in the value returned by "Csignals" is documented in the "comm.h" header file. EXAMPLES: if(!(Csignals() & DSR)) { Cclose(); abort("Modem not ready"); } CTESTC CTESTC PROTOTYPE: int Ctestc() ARGUMENTS: None RETURN VALUE: 0-255 - Character read from comm port -1 - No character available DESCRIPTION: This function tests for a character from the communications port previously opened with "Copen", and returns that character if one if found. If no character is available, "Ctestc" returns -1. EXAMPLES: if((c = Ctestc()) == -1) { Cclose(); abort("No character available"); } DISABLE DISABLE PROTOTYPE: disable(); ARGUMENTS: None RETURN VALUE: None DESCRIPTION: The "disable" function disables the 8086 interrupt system, preventing the processor from servicing interrupts. It is used whenever the execution of an interrupt handler may interfere with a particular operation. When this function is used, the "enable" function should be called as soon as possible after "disable". Failure to do this may result in loss of system functions performed under interrupts, such as timekeeping, and serial communications (Via MICRO-C serial drivers). EXAMPLES: disable(); /* Disallow interrupts */ Cflags &= ~TRANSPARENT; /* Remove transparency */ enable(); /* Re-allow interrupts */ ENABLE ENABLE PROTOTYPE: enable(); ARGUMENTS: None RETURN VALUE: None DESCRIPTION: The "enable" function enables the 8086 interrupt system, allowing the processor to service interrupts. It should be called as soon as possible following the use of the "disable" function. EXAMPLES: disable(); /* Disallow interrupts */ Cflags |= TRANSPARENT; /* Force transparency */ enable(); /* Re-allow interrupts */ EXEC EXEC PROTOTYPE: int exec(char *exefile, char *args) ARGUMENTS: exefile - Full pathname of a '.COM' or '.EXE' file args - Command tail containing arguments RETURN VALUE: 0 if successful, otherwise an MS-DOS error code DESCRIPTION: The "exec" function causes MS-DOS to suspend the execution of the MICRO-C program, and then to execute the indicated '.EXE' or '.COM' program file. When that program terminates, execution of the MICRO-C program will resume. This is a low level interface to the MS-DOS 'EXEC' function, and as such, it does not search your PATH, does not process '.BAT' files, nor provide any I/O redirection facilities. If you want to make use of these features (which are provided by 'COMMAND.COM'), use the higher level 'SYSTEM' function. EXAMPLES: printf("Type 'EXIT' to return to the MICRO-C program\n"); exec("C:\\COMMAND.COM", ""); /* Start up a sub-shell */ FREE_SEG FREE_SEG PROTOTYPE: int free_seg(int segment) ARGUMENTS: segment - A previously allocated segment of memory RETURN VALUE: 0 - The segment was released !0 - DOS error code DESCRIPTION: The "free_seg" function releases a segment of memory previously allocated by "alloc_seg", and returns it to the operating system. This should be used whenever your program has finished with a segment of extra memory which it has allocated. EXAMPLES: aseg = alloc_seg(4096); /* Allocate a 64K segment */ set_es(aseg); /* Set up extra segment */ asm_func(); /* Call assembler function */ free_seg(aseg); /* Releas the memory */ GET_ATTR GET_ATTR PROTOTYPE: int get_attr(char *pathname, int &attrs) ARGUMENTS: pathname- Name of file to get attributes of attrs - Integer to receive attributes RETURN VALUE: 0 if successful, otherwise an operating system error code DESCRIPTION: This function retreives the attributes of the specified file. The meaning of the individual bits in the "attrs" value is defined in the "file.h" header file. EXAMPLES: get_attr("tempfile", &attributes); GET_CS GET_CS PROTOTYPE: int get_cs() ARGUMENTS: None RETURN VALUE: The current processor CODE segment DESCRIPTION: This function is available only on the 8086 family of processors, and returns the current processor CODE segment. EXAMPLES: code_seg = get_cs(); GET_DATE GET_DATE PROTOTYPE: get_date(int &day, int &month, int &year) ARGUMENTS: &day - Address of integer to receive day (1-31) &month - Address of integer to receive month (1-12) &year - Address of integer to receive year (1980-2099) RETURN VALUE: None DESCRIPTION: This function gets the current system date in day, month, and year. EXAMPLES: get_date(&day, &month, &year); printf("%s %u, %u", months[month], day, year); GET_DRIVE GET_DRIVE PROTOTYPE: int get_drive() ARGUMENTS: None RETURN VALUE: The currently active (default) disk drive (0=A, 1=B, 2=C, ...) DESCRIPTION: The "get_drive" function returns the drive index (0-n) of the currently active or "default" MS-DOS disk drive. EXAMPLES: old_drive = get_drive(); set_drive(new_drive); GET_DS GET_DS PROTOTYPE: int get_ds() ARGUMENTS: None RETURN VALUE: The current processor DATA segment DESCRIPTION: This function is available only on the 8086 family of processors, and returns the current processor DATA segment. EXAMPLES: data_seg = get_ds(); GET_ES GET_ES PROTOTYPE: int get_es() ARGUMENTS: None RETURN VALUE: The current processor EXTRA segment DESCRIPTION: This function is available only on the 8086 family of processors, and returns the current processor EXTRA segment. EXAMPLES: code_seg = get_es(); GET_TIME GET_TIME PROTOTYPE: get_time(int &hour, int &minite, int &second) ARGUMENTS: &hour - Address of integer to receive hour (0-23) &minite - Address of integer to receive minite (0-59) &second - Address of integer to receive second (0-59) RETURN VALUE: None DESCRIPTION: This function gets the current system time in hours, minites and seconds. EXAMPLES: get_time(&hour, &minite, &second); printf("%02:%02:%02", hour, minite, second); RESIZE_SEG RESIZE_SEG PROTOTYPE: int resize_seg(int segment, int size) ARGUMENTS: segment - A previously allocated segment of memory size - Desired size (in 16 byte paragraphs) RETURN VALUE: 0 - The segments size has been adjusted !0 - DOS error code DESCRIPTION: The "resize_seg" function provides a method of changing the size of a segment of memory previously allocated via "alloc_seg". If not enough memory is available, the function will fail with a ono-zero return value. This function may also be used to adjust the memoey allocation of the programs image, by passing it the segment address of the programs own PSP. This value is available in the external variable "PSP". MICRO-C normally allocates 64K for programs compiled in the TINY model, and (64K + (256 byte PSP) + (size of executable code)) for programs compiled in the SMALL model. This allocation should NEVER be reduced, however you may enlarge it if your program wishes to access additional data immediately following its own DATA/STACK segment. EXAMPLES: extern int PSP; main() { if(resize_seg(PSP, 8192)) /* Append 64K buffer */ abort("Not enough memory!!!"); ... /* Remainder of program */ } RESTORE_VIDEO RESTORE_VIDEO PROTOTYPE: restore_video(char buffer[4006]); ARGUMENTS: buffer - Video save area. RETURN VALUE: None DESCRIPTION: The RESTORE_VIDEO function restores the contents and state of the IBM P.C. video display to the state it was in when "SAVE_VIDEO" was executed. At the present time, the function is effective only for text modes. Graphics screens will not be restored, due to the high memory requirements. Although this function is useful in ANY program (to restore the DOS screen before termination), it is most useful in "POP-UP" ram resident programs (See "TSR" function), to save the screen of any application which may be running when you pop up. The video state is restored from the passed "buffer" argument, which is 4006 bytes in size, and must have been filled in by "SAVE_VIDEO". It has the following format: buffer[0] - Video mode " [1] - Video page " [2] - 'X' cursor position " [3] - 'Y' cursor position " [4] - Ending line for cursor " [5] - Starting line for cursor " [6-4005] - Saved video screen contents EXAMPLES: popup_func() { save_video(); perform_function(); restore_video(); } SAVE_VIDEO SAVE_VIDEO PROTOTYPE: save_video(char buffer[4006]); ARGUMENTS: buffer - Video save area. RETURN VALUE: None DESCRIPTION: The SAVE_VIDEO function saves the current contents and state of the IBM P.C. video display. The screen may be restored at any time using "RESTORE_VIDEO". At the present time, the function is effective only for text modes. Graphics screens will not be saved, due to the high memory requirements. Although this function is useful in ANY program (to restore the DOS screen before termination), it is most useful in "POP-UP" ram resident programs (See "TSR" function), to save the screen of any application which may be running when you pop up. The video state is saved in the passed "buffer" argument, which is 4006 bytes in size, and has the following format: buffer[0] - Video mode " [1] - Video page " [2] - 'X' cursor position " [3] - 'Y' cursor position " [4] - Ending line for cursor " [5] - Starting line for cursor " [6-4005] - Saved video screen contents EXAMPLES: popup_func() { save_video(); perform_function(); restore_video(); } SET_ATTR SET_ATTR PROTOTYPE: int set_attr(char *pathname, int attrs) ARGUMENTS: pathname- Name of file to get attributes of attrs - New attributes RETURN VALUE: 0 if successful, otherwise an operating system error code DESCRIPTION: This function sets the system attributes of the specified file. The meaning of the individual bits in the "attrs" value is defined in the "file.h" header file. EXAMPLES: set_attr("tempfile", READONLY|HIDDEN); SET_DATE SET_DATE PROTOTYPE: set_date(int day, int month, int year) ARGUMENTS: day - New day (1-31) month - New month (1-12) year - New year (1980-2099) RETURN VALUE: 0 - Success -1 - Invalid date given DESCRIPTION: This function sets the current system date to day, month, and year. EXAMPLES: set_date(1, 1, 1980); /* Set to Jan 1, 1980 */ SET_DRIVE SET_DRIVE PROTOTYPE: int set_drive(int drive) ARGUMENTS: Drive - New drive index (0=A, 1=B, 2=C ...) RETURN VALUE: The total number of "logical" disk drives in the system DESCRIPTION: The "set_drive" function sets the disk drive indicated by the "drive" index (0-x) to be the currently active or "default" MS-DOS disk drive. EXAMPLES: old_drive = get_drive(); set_drive(new_drive); SET_ES SET_ES PROTOTYPE: int set_es(int segment) ARGUMENTS: segment - The 16 bit new segment value RETURN VALUE: None DESCRIPTION: This function is available only on the 8086 family of processors, and sets the processors EXTRA segment to the indicated value. EXAMPLES: set_es(get_ds()); /* Copy DATA to EXTRA segments */ SET_TIME SET_TIME PROTOTYPE: set_time(int hour, int minite, int second) ARGUMENTS: hour - New hour (0-23) minite - New minite (0-59) second - New second (0-59) RETURN VALUE: 0 - Success -1 - Invalid time given DESCRIPTION: This function sets the current system time to "hour", "minite" and "second". EXAMPLES: set_time(0, 0, 0); /* Set to 00:00:00 (midnight) */ TSR TSR PROTOTYPE: tsr(&func, int hotkey, int alloc) ARGUMENTS: func - Address of function to execute hotkey - POP-UP activation hotkeys alloc - Memory allocation RETURN VALUE: Function normally never returns, but if it does, an operating system error code is passed back. DESCRIPTION: The TSR function terminates the MICRO-C program, but leaves it resident in memory. When the specified "HOT KEYS" are detected on the IBM PC keyboard, the context of whatever program is running is saved, and the specified MICRO-C function is called. When that function returns, the interrupted program is resumed. When activated this way, THE "func" FUNCTION MUST NOT TERMINATE WITH "exit" or one of its related functions (abort etc.). THE ONLY WAY IT MAY TERMINATE IS TO "return" NORMALLY. The meaning of "hotkey" is defined in the "tsr.h" header file. The "alloc" paremeter specifies how much extra memory is to be retained in the TSR image for use by the MICRO-C stack and heap memory allocation functions. The "func" function(s) must insure that the total amount of memory used by the stack and calls to "malloc" does not exceed this value. NOTE: "malloc" will fail if the heap grows to within 1K of the stack pointer. All memory used by code, global variables, string space, and "malloc" calls prior to the use of "tsr" is automatically retained, and should not be included in the "alloc" value. TSR programs which perform screen I/O should take care to save and restore the screen contents when popping up and down. EXAMPLES: tsr(&popup_func, ALT+L_SHIFT, 1024); VCLEAR_BOX VCLEAR_BOX PROTOTYPE: vclear_box(int x, int y, int w, int h) ARGUMENTS: x - COLUMN of top left corner of box y - ROW of top left corner of box w - Width of box (columns) h - Height of box (rows) RETURN VALUE: None DESCRIPTION: This function clears a box of the specified height and width, at the indicated 'X' and 'Y' coordinates, on the IBM-PC video screen using the block graphics characters. The entire box is cleared to spaces. "VOPEN" MUST be called prior to using this function. EXAMPLES: vclear_box(21, 11, 8, 3); /* Clear a BOX */ VCLEOL VCLEOL PROTOTYPE: vcleol() ARGUMENTS: None RETURN VALUE: None DESCRIPTION: This function clears the IBM PC video screen from the current cursor position to the end of a line. You must "#include video.h", and execute "VOPEN" prior to using this function. EXAMPLES: vprintf("Input> "); /* Display a prompt */ vcleol(); /* Clear remainder of input line */ VCLEOS VCLEOS PROTOTYPE: vcleos() ARGUMENTS: None RETURN VALUE: None DESCRIPTION: This function clears the IBM PC video screen from the current cursor position to the end of a screen. "VOPEN" MUST be called prior to using this function. EXAMPLES: vgotoxy(0, 10); /* position at line 11 */ vcleos(); /* Clear lower part of screen */ VCLSCR VCLSCR PROTOTYPE: vclscr() ARGUMENTS: None RETURN VALUE: None DESCRIPTION: This function clears the entire IBM PC video screen and resets the cursor position to the top left hand corner. "VOPEN" MUST be called prior to using this function. EXAMPLES: if(c = 0x1b) { /* Escape command */ vclscr(); /* Clear the screen */ vprintf("%s has terminated\n", argv[0]); exit(-1); } VCURSOR_BLOCK VCURSOR_BLOCK PROTOTYPE: vcursor_block() ARGUMENTS: None RETURN VALUE: None DESCRIPTION: This function enables (turns on) display of the cursor on the IBM PC video display. The cursor is shown as flashing block, occupying the entire character window. "VOPEN" MUST be called prior to using this function. EXAMPLES: if(insert) /* Test insert mode flag */ vcursor_block(); /* Indicate inserting with block cursor */ else vcursor_line(); /* Indicate overwrite with line cursor */ VCURSOR_LINE VCURSOR_LINE PROTOTYPE: vcursor_line() ARGUMENTS: None RETURN VALUE: None DESCRIPTION: This function enables (turns on) display of the cursor on the IBM PC video display. The cursor is shown as a single flashing line, at the bottom of the character window. "VOPEN" MUST be called prior to using this function. EXAMPLES: vcursor_line(); /* Re-enable the cursor */ exit(0); /* And terminate */ VCURSOR_OFF VCURSOR_OFF PROTOTYPE: vcursor_off() ARGUMENTS: None RETURN VALUE: None DESCRIPTION: This function inhibits (turns off) display of the cursor on the IBM PC video display. This affects the cursor display only, screen output will continue to be displayed at the correct cursor position. "VOPEN" MUST be called prior to using this function. EXAMPLES: vclscr(); /* Clear screen */ vcursor_off(); /* Inhibit cursor */ vmenu(10, 10, main_menu, 0, &index); /* Present main menu */ VDRAW_BOX VDRAW_BOX PROTOTYPE: vdraw_box(int x, int y, int w, int h) ARGUMENTS: x - COLUMN of top left corner of box y - ROW of top left corner of box w - Width of box (columns) h - Height of box (rows) RETURN VALUE: None DESCRIPTION: This function draws a box of the specified height and width, at the indicated 'X' and 'Y' coordinates, on the IBM-PC video screen using the block graphics characters. "VOPEN" MUST be called prior to using this function. EXAMPLES: vdraw_box(20, 10, 10, 5); /* Draw a BOX */ VERSION VERSION PROTOTYPE: int version() ARGUMENTS: None RETURN VALUE: MS-DOS operating system version number DESCRIPTION: The "version" function is available only under MS-DOS, and returns the version number of the operating system. The higher 8 bits of the returned value indicates the MAJOR version number ('3' in DOS 3.1) The lower 8 bits of the returned value indicates the MINOR version nuber ('1' in DOS 3.1). EXAMPLES: if(version() < 0x031E) abort("Requires DOS 3.30 or higher\n"); VGETC VGETC PROTOTYPE: int vgetc() ARGUMENTS: None RETURN VALUE: 0-127 - ASCII value of key pressed < 0 - Special function key as defined in "video.h" DESCRIPTION: The "vgetc" function waits until a key is pressed on the system console, and returns its value. Note that due to the buffering of the IBM-PC keyboard, every keypress will be reported, even if the VGETC function is called after a key is pressed and released. EXAMPLES: switch(vgetc()) { /* Handle input keys . . . } VGETS VGETS PROTOTYPE: int vgets(int x, int y, char *prompt, char *field, int width) ARGUMENTS: x - COLUMN of top left corner of input box y - ROW of top left corner of input box prompt - String to prompt with field - String to receive the data width - Width in characters of input field RETURN VALUE: 0 - Selection was made and ENTER pressed. !0 - Input was aborted via ESCAPE key. DESCRIPTION: The "vgets" function draws a box on the video screen at the specified X and Y coordinates, then prompts for and receives an input string in the box. The box is drawn large enough to contain the prompt and the specified width of input field. The prompt is displayed at the left hand side of the box, and the cursor is positioned immediatly following it, at the start of the input field. The "field" parameter is the address of a character array to receive the input string. The previous value of the "field" array is inserted into the input box when VGETS is invoked. If you do not want to display an old value, you should set the first character pointed to by field to zero, before calling VGETS. When entering the string, the user may use the following special keys to edit the input field: Right Arrow - Move forward one character Left Arrow - Move backward one character Delete - Delete the character under the cursor Backspace - Move backward one character and delete. Home - Move to beginning of string End - Move to end of string PgUp - Clear (erase) entire string PgDn - Clear from cursor to end of string Enter - Accept (enter) the string ESC - Abort the input request All data entered in the input box is inserted into any data which is already present. EXAMPLES: name[0] = 0; if(vgets(10, 10, "Your name?", name, 30)) return; /* Aborted, exit to higher level */ VGOTOXY VGOTOXY PROTOTYPE: vgotoxy(int x, int y) ARGUMENTS: x - New COLUMN (0-79) y - New ROW (0-24) RETURN VALUE: None DESCRIPTION: The "vgotoxy" function positions the cursor on the IBM-PC video screen. Any further display output will occur at the new ROW and COLUMN on the screen. The extern "int" variable "V_XY" may be referenced to read or set the current X/Y position. The higher 8 bits contain the 'Y' coordinate, and the lower 8 bits contain the 'X' coordinate. If this variable is used to set (restore) the cursor position, "vupdatexy" must then be called to position the physical cursor. "VOPEN" MUST be called prior to using this function. EXAMPLES: for(i=0; i<24; ++i) { /* Draw a diagonal line of 'X's */ vgotoxy(i, i); vputc('X'); } VMENU VMENU PROTOTYPE: vmenu(int x, int y, char *names[], char erase, int &index) ARGUMENTS: x - COLUMN of top left corner of menu box y - ROW of top left corner of menu box names - Array to menu selection text (last entry = 0) erase - 1=Erase BOX after selection is made index - Address of message selection index variable RETURN VALUE: 0 - Selection was made and ENTER pressed. !0 - Menu was aborted via ESCAPE key. DESCRIPTION: The "vmenu" function displays a list of menu items enclosed in a box on the IBM-PC video screen at the specified ROW and COLUMN address. The user may use the UP, DOWN, HOME and END keys to select an entry by moving the INVERSE VIDEO selection cursor. When the desired selection is under the cursor, the selection is made by pressing the ENTER key. At any time the menu selection may be canceled by pressing the ESCAPE key. The "names" argument must be a pointer to an array of character strings which are the selections to display. This array MUST end with a zero (0) element to indicate the end of the list. The "erase" flag indicates that the menu box should be cleared to blanks when the selection is made. If "erase=0", the menu box is left on the screen, WITHOUT the selection cursor, with the selected entry marked by '>' and '<'. The menu box is always erased when the menu is aborted with the ESCAPE key. The "index" argument is the address of an "int" variable which contains the position of the selection cursor. It controls where the selection cursor will appear when the function is first invoked (0 = first entry), and also is assigned the position of the selection cursor when the selection is made. EXAMPLES: char *names[] = { "One", "Two", "Three", "Four", "Five", 0 }; . . . index = 0; if(vmenu(10, 10, names, 0, &index)) return; /* Aborted, exit to higher level */ switch(index) { /* Handle selection */ . . . } VMESSAGE VMESSAGE PROTOTYPE: vmessage(int x, int y, char *string) ARGUMENTS: x - COLUMN of top left corner of message box y - ROW of top left corner of message box string - Message to display RETURN VALUE: None DESCRIPTION: The "vmessage" function displays a text string surrounded by a BOX, on the IBM-PC video screen, at the specified ROW and COLUMN address. "VOPEN" MUST be called prior to using this function. EXAMPLES: vmessage(20, 20, "Press any KEY to continue"); get_key(); vclear_box(20, 20, 26, 2); VOPEN VOPEN PROTOTYPE: vopen() ARGUMENTS: None RETURN VALUE: None DESCRIPTION: This function initializes the IBM-PC video display adapter for use with the MICRO-C video library functions. It determines the adapter type (COLOR ot MONOCHROME), sets up internal variables with information required by the other video functions, and clears the video screen. This function MUST be called before any of the other video functions in the library are used. After "vopen" is called, the extern "int" variable "V_BASE" may be referenced to determine the memory segment of the video display (B000 for monochrome, B800 for color). Any program using the video library functions must include the "video.h" header file. EXAMPLES: vopen(); VPRINTF VPRINTF PROTOTYPE: register vprintf(char *format, arg, ...) ARGUMENTS: format - Pointer to format string arg - Argument as determined by format string ... - Additional arguments may be required RETURN VALUE: None DESCRIPTION: This function performs exactly as the "PRINTF" function in the standard function library, except that it outputs directly to the video screen using the video interface library routines. This function should be used in preference to "PRINTF" when using the video function library since "PRINTF" will not move the video librarys cursor. NOTE: This function uses a variable number of arguments, and must be declared as "register" (See "video.h"). "VOPEN" MUST be called prior to using this function. EXAMPLES: vgotoxy(0, 0); vprintf("Screen %u", screen); VPUTC VPUTC PROTOTYPE: vputc(char chr) ARGUMENTS: chr - Character to display RETURN VALUE: None DESCRIPTION: This function displays a character on the video screen at the current cursor position. Characters are output in "tty" fashion, with proper handling of control codes such as CARRIAGE-RETURN, LINE-FEED and BELL. The screen will scroll upwards when a NEWLINE is printed on the bottom line of the screen, or when the bottom line wraps around to the next. Although only the lower 8 bits of a passed value are used, "vputc" will not perform ANY output translations if any of the upper 8 bits are set. This provides a method of displaying the video characters represented by control codes such as NEWLINE, and BACKSPACE. The external "char" variable "V_ATTR" may be used to set the video attribute used by "VPUTC" to display the character. This value is written to the attribute location associated with the character on the video display hardware. Its effect is dependant on the video adapter in use. The "video.h" header file contains definitions of the attribute bits for use on "standard" monochrome and color displays. "VOPEN" MUST be called prior to using this function. EXAMPLES: vputc(0x0A); /* Line-feed, advance cursor */ vputc(0x0A | 0xff00); /* Display 0x0A character code */ VPUTF VPUTF PROTOTYPE: vputf(char *string, int width) ARGUMENTS: string - Pointer to character string width - Width of output field RETURN VALUE: None DESCRIPTION: The "vputf" function outputs a character string to the IBM-PC video screen using the video library functions. The string is left justified in a field of the specified width. If the string is shorter than "width", the field is padded with blanks. If the string is longer than "width", the output is truncated. "VOPEN" MUST be called prior to using this function. EXAMPLES: vputf(message, 10); VPUTS VPUTS PROTOTYPE: vputs(char *string) ARGUMENTS: string - Pointer to character string RETURN VALUE: None DESCRIPTION: The "vputs" function outputs a character string to the IBM-PC video screen using the video library functions. "VOPEN" MUST be called prior to using this function. EXAMPLES: vputs(message); VTSTC VTSTC PROTOTYPE: int vtstc() ARGUMENTS: None RETURN VALUE: 0 - No key pressed 1-127 - ASCII value of key pressed < 0 - Special function key as defined in "video.h" DESCRIPTION: The "vtstc" function tests for a key pressed on the system console, and returns its value. A returned value of zero (0) indicates that no key was found to be pressed. Note that due to the buffering of the IBM-PC keyboard, every keypress will be reported, even if the VTSTC function is called after a key is pressed and released. EXAMPLES: if(vtstc() == 0x1B) /* exit loop on ESCAPE key */ break; VUPDATEXY VUPDATEXY PROTOTYPE: vupdatexy() ARGUMENTS: None RETURN VALUE: None DESCRIPTION: This function updates the real X/Y cursor position on the video screen to reflect the "logical" position where the next character will be output. The MICRO-C video library uses a BIOS interrupt (INT 10) to position the cursor, which is quite slow, compared to the speed of the library video routines. To prevent this from slowing down the video output, the cursor is only physically re-positioned when a "vgotoxy" or a "vgetc" is executed. This allows the library routines to run at full speed, and still put the cursor in the right place when output stops and an input request is made. A side effect of this is that the cursor on the screen will not appear to move unless you call "vgotoxy" or "vgetc". This only affects the physical cursor on the screen, MICRO-C maintains its own internal cursor location which it uses to determine where on the screen the next write will occur. Some applications which run in real time (Such as a terminal emulator) do not call "vgetc", but use "vtstc" to poll the keyboard on a regular basis. In this case, the "vupdatexy" routine should be called any time that the visual position of the cursor is important. "VOPEN" MUST be called prior to using this function. EXAMPLES: vupdatexy(); /* position the cursor * c = vtstc(); /* Test for a character */ MICRO-C Library Page: 4 +------------------------------------+ | | | ******************************** | | * The IBM-PC WINDOWING library * | | ******************************** | | | +------------------------------------+ 1.3 IBM-PC WINDOWING Library The MICRO-C WINDOWING LIBRARY is a set of powerful, very fast, compact, text based windowing functions for use with the MICRO-C compiler, on the IBM Personal Computer. Features of the library include multiple open windows, overlaid windows with automatic save/restore of screen underneath, scrolling within windows, optional window borders, menu and form entry functions, and more. The library is organized into two parts, the first is a set of assembly language routines which provides the basic "low level" functions to open/close windows, and to output data in them. The second part of the library provides a set of 'C' functions which provide "high level" functions such as menu and form entry, formatted printing, etc. MICRO-C Library Page: 5 1.3.1 Window Control Block Whenever a new window is opened, the windowing library sets up a WINDOW CONTROL BLOCK (WCB) which contains information needed to access and control the window. The format of the WCB is: Offset: 0 - Current video attribute * 1 - Window flags (High 8 bits of w_open attrs) ** 2 - Absolute 'X' position of top left corner of active region. *** 3 - Absolute 'Y' position of top left corner of active region. *** 4 - Width in characters of active region *** 5 - Height in characters of active region *** 6 - Current 'X' cursor coordinate 7 - Current 'Y' cursor coordinate 8,9 - Pointer to previous window buffer 10 - Previous cursor ENDING line 11 - Previous cursor STARTING line 12 - Previous cursor absolute 'X' position **** 13 - Previous cursor absolute 'Y' position **** 14..- Save area for SAVE/RESTORE function * You may dynamically alter the video attribute of data written to the window by writing to this byte. ** You may dynamically alter the properties of the window by setting or clearing the flag bits with these exceptions: -DO NOT enable SAVE/RESTORE unless opened with it (It is Ok to disable SAVE/RESTORE). -DO NOT change the state of the BORDER bits. *** For windows opened with a BORDER, this reflects the size of the active region (not including the border). Otherwise, this is the size of the entire window. **** For full screen window which does not SAVE/RESTORE, you can set these values to zero to home cursor on exit. MICRO-C Library Page: 6 1.3.2 External Variables In addition to the functions decribed on the following pages, the windowing library provides the following external variables which may be accessed from within your 'C' program: 1.3.2.1 W_BASE extern int W_BASE; This variable contains the base address of the video screen, which may be used to determine the type of display present: B000 = Monochrome B800 = Color 1.3.2.2 W_OPEN extern char *W_OPEN; This variable contains a pointer to the WCB for the "active" window, and controls which window is manipulated by certain library functions. This automatically set up by "wopen" to point to the last window opened, but may be changed at any time with: W_OPEN = window; NOTE, when the active window is closed, W_OPEN is reset to point to the window which was active at the time that it (the active window) was opened. If windows are closed in other than the reverse order of which they were opened, W_OPEN may be left pointing to a window which has already been closed. If this happens, YOU MUST NOT USE THE "ACTIVE" WINDOW FUNCTIONS WITHOUT RESETTING W_OPEN TO POINT TO AN OPEN WINDOW. It is your (the programmer's) responsibility to insure that you know what window will be accessed through W_OPEN at all times throughout your program. 1.3.3 Window Library Functions The following pages contain a description of each function available in the IBM-PC windowing library. WCLEOL WCLEOL W_CLEOL W_CLEOL PROTOTYPE: wcleol() w_cleol(char *window) ARGUMENTS: window - Pointer to WCB for an open window RETURN VALUE: None DESCRIPTION: The "wcleol" function clears the active window from the current cursor position to the end of a line. The "w_cleol" function clears the specified window fromt the current position to the end of the line. EXAMPLES: wputs("Input> "); /* Display a prompt */ wcleol(); /* Clear remainder of input line */ WCLEOW WCLEOW W_CLEOW W_CLEOW PROTOTYPE: wcleow() w_cleow(char *window) ARGUMENTS: window - Pointer to WCB for an open window RETURN VALUE: None DESCRIPTION: The "wcleow" function clears the active window from the current position to the end of the window. The "w_cleow" function clears the specified window from the current position to the end of the window. EXAMPLES: wgotoxy(0, 10); /* position at line 11 */ wcleos(); /* Clear lower part of screen */ WCLOSE WCLOSE W_CLOSE W_CLOSE PROTOTYPE: wclose() w_close(char *window) ARGUMENTS: window - Pointer to WCB for an open window RETURN VALUE: None DESCRIPTION: The "wclose" function closes the "active" window, and de-activates it. The "w_close" function closes the specified window, and de-activates it. If the window being closed is the "active" window, the "active" window will revert to the window which was "active" at the time that the window being closed was opened. EXAMPLES: wclose(); /* Close active window */ w_close(title); /* Close the title window */ WCLWIN WCLWIN W_CLWIN W_CLWIN PROTOTYPE: wclwin() w_clwin(char *window) ARGUMENTS: window - Pointer to WCB for an open window RETURN VALUE: None DESCRIPTION: The "wclwin" function clears the entire active window and resets the cursor position to the top left hand corner. The "w_clwin" function clears the entire specified window, and resets the cursor position to the top left hand corner. EXAMPLES: if(c = 0x1b) { /* Escape command */ wclwin(); /* Clear the screen */ wputs("Exiting back to main menu"); return; } WCURSOR_BLOCK WCURSOR_BLOCK PROTOTYPE: wcursor_block() ARGUMENTS: None RETURN VALUE: None DESCRIPTION: This function enables (turns on) display of the cursor on the IBM PC video display. The cursor is shown as flashing block, occupying the entire character window. EXAMPLES: if(insert) /* Test insert mode flag */ wcursor_block(); /* Indicate inserting with block cursor */ else wcursor_line(); /* Indicate overwrite with line cursor */ WCURSOR_LINE WCURSOR_LINE PROTOTYPE: wcursor_line() ARGUMENTS: None RETURN VALUE: None DESCRIPTION: This function enables (turns on) display of the cursor on the IBM PC video display. The cursor is shown as a single flashing line, at the bottom of the character window. EXAMPLES: wcursor_line(); /* Re-enable the cursor */ exit(0); /* And terminate */ WCURSOR_OFF WCURSOR_OFF PROTOTYPE: wcursor_off() ARGUMENTS: None RETURN VALUE: None DESCRIPTION: This function inhibits (turns off) display of the cursor on the IBM PC video display. This affects the cursor display only, screen output will continue to be displayed at the correct cursor position. EXAMPLES: wclscr(); /* Clear screen */ wcursor_off(); /* Inhibit cursor */ wmenu(10, 10, 0x6007, main_menu, &index); /* Present main menu */ WFORM WFORM PROTOTYPE: register wform(int x, int y, int attrs, char *prompts[], char *strings, ...) ARGUMENTS: x - Absolute COLUMN of upper left corner of form window y - Absolute ROW of upper left corner of form window attrs - Attributes for form window (See WOPEN) prompts - Prompt string for form entries strings - Destination string to receive form data ... - Additional arguments may be required RETURN VALUE: None DESCRIPTION: The "wform" function opens a window, which contains a "form" consisting of prompts and data areas. Each data area is shown beside its corresponding prompt, and may be edited using the keys supported by WGETS. the UP and DOWN ARROW keys may be used to move the editing cursor between the various fields in the input form.* The "attrs" argument contains the open attributes (see WOPEN) for the menu window, and may be used to control the color, border, clearing, etc. The "prompts" argument is an array of pointers to strings, which define the prompts and input fields in the form. The first two characters of each string define the 'X' and 'Y' coordinates within the window of the prompt string. The third character contains the length of the destination string, and the remainder of the string contains the text prompt. The destination string is positioned in the window directly following the prompt string. This list of prompts must end with a NULL (0) element. The first (0) element of "prompts" does not actually point to an input definition, but contains the X and Y sizes for the window to be opened (High byte = X, Low byte = Y). Following the "prompts" argument, there must be one destination "string" argument for each prompt defined. The strings must be long enough to contain the number of characters specified in the third byte of the coresponding "prompt" string. Only the lower seven bits of the field length are used (length = 1-127), the high bit indicates that the field is to contain numbers only. In this case, the corresponding argument is NOT a pointer to a string, but must be a pointer to an "int" variable. The form is exited by pressing the ESCAPE key. EXAMPLES: /* Sample input form */ char *form[] = { 50<<8|6, /* Place in 50 by 6 window */ "\x01\x00\x20Software :", "\x01\x01\x20Author :", "\x01\x02\x20Directory :", "\x01\x03\x20Filename :", 0 }; /* Data areas for input form */ char software[0x21] = "MICRO-C", author[0x21] = "Dave Dunfield", direct[0x21] = "C:\\MC", filename[0x21] = "MC*.*"; /* Simple main program to display the form */ main() { wform(15, 9, 0xE007, form, software, author, direct, filename); } WGETC WGETC W_GETC W_GETC PROTOTYPE: int wgetc() int w_getc(char *window) ARGUMENTS: window - Pointer to WCB for an open window RETURN VALUE: 0-127 - ASCII value of key pressed < 0 - Special function key as defined in "video.h" DESCRIPTION: The "wgetc" function waits until a key is pressed on the system console, and returns its value. The cursor is updated to be placed at the current cursor position in the active window. The "w_getc" function waits until a key is pressed on the system console, and returns its value. The cursor is updated to be placed at the current cursor position in the specified window. Note that due to the buffering of the IBM-PC keyboard, every keypress will be reported, even if the WGETC or W_GETC function is called after a key is pressed and released. EXAMPLES: switch(wgetc()) { /* Handle input keys . . . } WGETS WGETS PROTOTYPE: int wgets(int x, int y, char *string, int length) ARGUMENTS: x - COLUMN position for input y - ROW position for input string - Destination string length - Length of string (High bit set = Numbers only) RETURN VALUE: Character causing exit DESCRIPTION: The "wgets" function positions the cursor at the specified X and Y coordinates, and displays the contents of "string" (in a field of "length" characters), and waits for input, which may be used to edit the string. Any normal ASCII characters which are input will be entered into the string, The following function keys are recognized: LEFT ARROW - Position cursor one space to the left RIGHT ARROW - Position cursor one space to the right BACKSPACE - Backup cursor & delete previous character DELETE - Delete character under cursor INSERT - Toggle between INSERT/OVERWRITE HOME - Position cursor at start of string END - Position cursor at end of scring PAGE UP - Clear entire field PAGE DOWN - Clear from cursor to end of field Any other special function keys will cause "wgets" to terminate, and return the value of the offending key. (See "window.h" for key definitions). When INSERT mode is enabled, all entered text will be inserted into the string, with the remainder of the string shifting to the right. This mode is indicated by a flashing BLOCK cursor. When OVERWRITE mode is enabled, all entered text will overwrite the existing string. This mode is indicated by a flashing LINE cursor. EXAMPLES: wgets(2, 5, name, 25); WGOTOXY WGOTOXY W_GOTOXY W_GOTOXY PROTOTYPE: wgotoxy(int x, int y) w_gotoxy(int x, int y, char *window) ARGUMENTS: x - New COLUMN y - New ROW window - Pointer to WCB for an open window RETURN VALUE: None DESCRIPTION: The "wgotoxy" function positions the cursor within the active window. Any further display output to that window will occur at the new ROW and COLUMN positions. The "w_gotoxy" function positions the cursor within the specified window. Any further display output to that window will occur at the new ROW and COLUMN positions. EXAMPLES: for(i=0; i<10; ++i) { /* Draw a diagonal line of 'X's */ wgotoxy(i, i); wputc('X'); } WMENU WMENU PROTOTYPE: wmenu(int x, int y, int attrs, char *names[], int &index) ARGUMENTS: x - Absolute COLUMN of top left corner of menu window y - Absolute ROW of top left corner of menu window attrs - Attributes for menu window (see WOPEN) names - Array to menu selection text (last entry = 0) index - Address of message selection index variable RETURN VALUE: 0 - Selection was made and ENTER pressed. !0 - Menu was aborted via ESCAPE key. DESCRIPTION: The "wmenu" function opens a window containing a list of menu items at the specified ROW and COLUMN address. The user may use the UP, DOWN, HOME and END keys to select an entry by moving the INVERSE VIDEO selection cursor. Pressing an alpha-numeric key will position the selection bar to the first entry which begins with that character. When the desired selection is under the cursor, the selection is made by pressing the ENTER key. At any time the menu selection may be canceled by pressing the ESCAPE key. The "attrs" argument contains the open attributes (see WOPEN) for the menu window, and may be used to control the color, border, clearing, etc. The "names" argument must be a pointer to an array of character strings which are the selections to display. This array MUST end with a NULL (0) element to indicate the end of the list. The "index" argument is the address of an "int" variable which contains the position of the selection cursor. It controls where the selection cursor will appear when the function is first invoked (0 = first entry), and also is assigned the position of the selection cursor when the selection is made. Once a selection is made, the first character of that selection will be hilighted in reverse video. EXAMPLES: char *names[] = { "One", "Two", "Three", "Four", "Five", 0 }; . . . index = 0; if(wmenu(10, 10, 0xE007, names, &index)) return; /* Aborted, exit to higher level */ switch(index) { /* Handle selection */ . . . } WOPEN WOPEN PROTOTYPE: char *wopen(int x, int y, int width, int height, int attrs) ARGUMENTS: x - Absolute COLUMN of top left corner of window y - Absolute ROW of top left corner of window width - The width of the window in characters height - The height of the window in characters attrs - The window attributes, BIT definitions: 15 - Enable SAVE/RESTORE screen under window * 14 - Enable SINGLE line BORDER * 13 - Enable DOUBLE line BORDER 12 - Enable CLEAR on OPEN ** 11 - Enable CLEAR on CLOSE *** 10 - Disable NEWLINE (LF only) 9 - Enable SCROLLING in window 8 - Enable LINE WRAP in window 7-0 - Video attributes for window * When BORDER is selected, window will include an enclosing BOX. In this case, the effective height and width of the active region (where text data can be written) will be reduced by 2. ** Has no visual effect when SAVE/RESTORE is enabled. *** If this BIT is set, CTRL-J will behave as LINEFEED only, and will not return the cursor to the left margin. RETURN VALUE: A pointer to the WCB for the newly opened window 0 if the window could not be opened DESCRIPTION: The "wopen" function creates a new window on the PC video screen. This newly created window is also made the "active" window, which is automatically accessed by many of the windowing functions. If "wopen" is unable to allocate enough memory for the window control block (WCB), it will fail and return a value of zero (0). EXAMPLES: /* Create a title window at top of screen */ titlewin = wopen(0, 0, 80, 3, 0x6047); WPRINTF WPRINTF W_PRINTF W_PRINTF PROTOTYPE: register wprintf(char *format, arg, ...) register w_printf(char *window, char *format, arg, ...) ARGUMENTS: window - Pointer to WCB for an open window format - Pointer to format string arg - Argument as determined by format string ... - Additional arguments may be required RETURN VALUE: None DESCRIPTION: The "wprintf" function performs exactly as the "PRINTF" function in the standard function library, except that it outputs directly to the active window using the low level windowing library functions. The "w_printf" function behaves similar to "wprintf", except that the window to receive the output is specified as the first parameter. These functions should be used in preference to "PRINTF" when using the windowing function library since "PRINTF" will not move the windowing librarys cursor, will not use the attributes from the WCB, and will not respect the boundarys of the window. NOTE: This function uses a variable number of arguments, and must be declared as "register" (See "window.h"). EXAMPLES: wgotoxy(0, 0); wprintf("Window %u", screen); WPUTC WPUTC W_PUTC W_PUTC PROTOTYPE: wputc(int c) wputc(int c, char *window) ARGUMENTS: c - Character to be written to window RETURN VALUE: None DESCRIPTION: This "wputc" function displays a character in the active window at the current cursor position. The "w_putc" functino displays a character in the specified window at the current cursor position. Characters are output in "tty" fashion, with proper handling of control codes such as CARRIAGE-RETURN, LINE-FEED and BELL. The screen will scroll upwards when a NEWLINE is printed on the bottom line of the screen, or when the bottom line wraps around to the next (Assuming those options are enabled in the window). Although only the lower 8 bits of a passed value are used, "vputc" will not perform ANY output translations if any of the upper 8 bits are set. This provides a method of displaying the video characters represented by control codes such as NEWLINE, and BACKSPACE. The first byte of the window control block (WCB) for the window contains the attributes which will be used to display the character. This value is written to the attribute location associated with the character on the video display hardware. Its effect is dependant on the video adapter in use. The "window.h" header file contains definitions of the attribute bits for use on "standard" monochrome and color displays. EXAMPLES: w_putc(0x0A, window1); /* Line-feed, advance cursor */ wputc(0x0A | 0xff00); /* Display 0x0A character code */ WPUTF WPUTF PROTOTYPE: wputf(char *string, int width) ARGUMENTS: string - Pointer to character string width - Width of output field RETURN VALUE: None DESCRIPTION: The "wputf" function outputs a character string to the active window screen using the video library functions. The string is left justified in a field of the specified width. If the string is shorter than "width", the field is padded with blanks. If the string is longer than "width", the output is truncated. EXAMPLES: wputf(message, 10); WPUTS WPUTS W_PUTS W_PUTS PROTOTYPE: wputs(char *string) w_puts(char *string, char *window) ARGUMENTS: string - Pointer to character string window - Pointer to WCB for an open window RETURN VALUE: None DESCRIPTION: The "wputs" function outputs a character string to the active window. The "w_puts" function output a character string to the specified window. EXAMPLES: wputs(message); w_puts(message, window1); WTSTC WTSTC W_TSTC W_TSTC PROTOTYPE: int wtstc() int w_tstc(char *window) ARGUMENTS: window - Pointer to WCB for an open window RETURN VALUE: 0 - No key pressed 1-127 - ASCII value of key pressed < 0 - Special function key as defined in "video.h" DESCRIPTION: The "wtstc" function tests for a key pressed on the system console, and returns its value. If a character is found, the cursor is updated in the active window. The "w_tstc" function tests for a key pressed on the system console, and returns its value. If a character is found, the cursor is updated in the specified window. A returned value of zero (0) indicates that no key was found to be pressed. Note that due to the buffering of the IBM-PC keyboard, every keypress will be reported, even if the WTSTC or W_TSTC function is called after a key is pressed and released. EXAMPLES: if(wtstc() == 0x1B) /* exit loop on ESCAPE key */ break; WUPDATEXY WUPDATEXY W_UPDATEXY W_UPDATEXY PROTOTYPE: wupdatexy() w_updatexy(char *window) ARGUMENTS: window - Pointer to WCB for an open window RETURN VALUE: None DESCRIPTION: The "wupdatexy" function updates the real X/Y cursor position on the video screen to reflect the "logical" position where the next character will be output in the active window. The "w_updatexy" function updates the real X/Y cursor position on the video screen to reflect the "logical" position where the next character will be output in the specified window. The MICRO-C Windowing library uses a BIOS interrupt (INT 10) to position the cursor, which is quite slow, compared to the speed of the library video routines. To prevent this from slowing down the video output, the cursor is only physically re-positioned when a "wgotoxy" or a "wgetc" is executed. This allows the library routines to run at full speed, and still put the cursor in the right place when output stops and an input request is made. A side effect of this is that the cursor on the screen will not appear to move unless you call "wgotoxy" or "wgetc". This only affects the physical cursor on the screen, MICRO-C maintains its own internal cursor location which it uses to determine where on the screen the next write will occur. Some applications which run in real time (Such as a terminal emulator) do not call "wgetc", but use "wtstc" to poll the keyboard on a regular basis. In this case, the "wupdatexy" routine should be called any time that the visual position of the cursor is important. EXAMPLES: wupdatexy(); /* position the cursor * c = wtstc(); /* Test for a character */ MICRO-C Library TABLE OF CONTENTS Page 1. THE MICRO-C LIBRARIES 1 1.1 STANDARD Library 2 1.2 IBM-PC/MS-DOS Library 3 1.3 IBM-PC WINDOWING Library 4