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PSEDIT Binary File Editor USER'S GUIDE Copyright 1990, 1993 by Gary C. Crider and Parity Solutions TABLE OF CONTENTS: What is PSEDIT? .................................. 1.0 Customizing PSEDIT ............................... 2.0 The PSEDIT.INI Configuration File .............. 2.1 The PSEDIT Command Line and Switches ........... 2.2 Customizing On A Network ....................... 2.3 Operational Notes and Requirements................ 3.0 The Keyboard and Display ......................... 4.0 Modifying Data ................................... 5.0 Filling a block of data ........................ 5.1 Deleting Data .................................... 6.0 Inserting Data ................................... 7.0 Using the clipboard (Cut, Paste, Copy) ........... 8.0 Locating Data .................................... 9.0 Go to a Position in the File ................... 9.1 Search for Data ................................ 9.2 Find and Replace Data .......................... 9.3 Print the File ................................... 10.0 Save the File .................................... 11.0 Hex/Decimal Conversions and Calculations.......... 12.0 Exiting PSEDIT ................................... 13.0 Help ............................................. 14.0 A Useful Example - Modification of DOS 5's EDIT ................... 15.0 Installation ..................................... Appendix A Disclaimer ....................................... Appendix B Support .......................................... Appendix C Registration ..................................... Appendix D 1.0 What Is PSEDIT? One thing most of us learned early while working on our first PC was that EDLIN, while useful, stank (stunk?)... was malodorous as an editor of text files. Soon there were hundreds of full screen text editors available everywhere. Even Microsoft finally came around and included EDIT in DOS 5 to get us away from EDLIN. An early lesson that most who aspire to be power users learn is that not all changes we desire to make are in text files. Sooner or later we end up patching an executable program, database, or strange format file that text editors will not handle. Enter DEBUG. Just as EDLIN was a pain for editing text files, DEBUG is a pain for editing binary files. Strangely, few people have jumped out with binary editors and some of the few I have seen are not much better than DEBUG. PSEDIT is a very easy-to-use full screen editor for binary (or text) files. You simply type over the hex or ASCII data much as you would with any text editor. PSEDIT ensures that you enter hex characters (0-9 and A-F) while you are in hex entry mode. You will be able to see the hex and ASCII representations at all times whether you are editing in hex or ASCII. Using PSEDIT is so intuitive, I don't know why I'm writing this documen- tation or why you are reading it. Perhaps we both like to move cautiously. You see a full screen of data at all times, not just a few bytes. Paging through the file is as easy as hitting PgUp and PgDn, you don't have to enter hex displacements to get to the next page. I think you'll find, as we have at a Fortune 100 company (my day job), that PSEDIT becomes one of the handiest tools you have. You will use it much more than you now expect that you will. PSEDIT automatically detects and uses any available conventional, expanded or extended memory. It will also use disk space to simulate memory when it runs short. This shared memory pool is referred to as virtual memory. It allows very large files to be edited (up to 64 megabytes). PSEDIT was formerly distributed under the name BEDIT. 2.0 Customizing PSEDIT There are two ways to customize PSEDIT to fit your preferences and your environment. The first and most recommended is to make your settings in the PSEDIT.INI file. These become your default settings. Sometimes you may want to override one or more of them temporarily. The command line switches will override the PSEDIT.INI file. More options are configurable in the PSEDIT.INI file than with command line switches. 2.1 The PSEDIT.INI Configuration File A sample PSEDIT.INI file comes with PSEDIT and is initialized to all of the defaults. The defaults are used when the PSEDIT.INI file cannot be found or when a particular setting is missing from the file. The PSEDIT.INI file can be changed with any text file editor and should be saved in a directory that is specified in DOS's PATH= environment variable. Or you can use a SET statement such as follows to tell PSEDIT where to look for the PSEDIT.INI file: SET PSEINI=D:\PSEDIT\ Do not specify a file name, only the directory where PSEDIT.INI is located. The trailing backslash is only required if you want to specify a root directory. Place the SET statement in your AUTOEXEC.BAT file. If the PSEDIT.INI file is in a directory on your path, you do not need to use the PSEINI= environment variable. As a last resort, if PSEDIT.INI is not found on the path or in a PSEINI= variable, it also looks in the same directory from which PSEDIT.EXE was loaded. Thus, if you keep PSEDIT.EXE and PSEDIT.INI in the same directory, PSEDIT should never have trouble locating it. You have a lot of latitude in where to place the PSEDIT.INI file, but try to only have one, as you can get confused as to which one is being used if there is more than one. All of the settings and values for the PSEDIT.INI file are documented within the PSEDIT.INI file provided with PSEDIT.EXE. If you wish to add comments to the file, the first non-blank character on the line should be a semi-colon (;). 2.2 The PSEDIT Command Line and Switches Format: PSEDIT [[path]filename] [/B] [/I] [/V /?] The filename is the file name of the file that you want to edit. The path is required if a file is specified and is not in the current directory. See BackupMode= in the PSEDIT.INI file for information about automatic or prompted backups of the file. If no file name is specified, a pick list is displayed of all of the files in the current directory. To select a file, use the arrow keys to move the selection bar to the file you want, and press enter. If a file is specified, but not found, a pick list will be displayed of all files in the specified directory. /? Display command line help prompt. /B reverses the effect of the MonochromeVideo setting in PSEDIT.INI. If you have specified monochrome display, /B forces color display. If you have not selected monochrome, black and white (monochrome) display is forced. /I reverses the effect of the InternationalChars setting in PSEDIT.INI. if you have specified international characters, /I will cause international characters to not be recognized. If you have not specified international characters, /I forces recognition of international characters. /G reverses the effect of the GraphicsChars setting in PSEDIT.INI. If you have specified graphics characters, /G will cause international and graphics characters to not be recognized. If you have not specified graphics characters, /G forces recognition of international and graphics characters. /V reverses the effect of the BIOSWrites setting in PSEDIT.INI. If you have specified BIOS writes, /V will force direct video memory reads and writes for the edit window. If you have not specified BIOS writes, /V will force BIOS reads and writes. Brackets ([]) indicate optional parameters. Do not include the brackets in the command line. 2.3 Customizing On A Network In a LAN environment, PSEDIT would normally be installed on a file server in a directory that is on the search path. A master copy of the PSEDIT.INI file should also be in this directory and will have the default config- uration for all users. In order for an individual user to customize PSEDIT without impacting others, use the PSEINI= environment variable to point to a local or private directory that will contain the PSEDIT.INI file to be used. The PSEINI= variable does not have to be specified if the personal PSEDIT.INI file is placed in a directory that precedes the directory with the master INI file in the search path. 3.0 Operational Notes and Requirements PSEDIT's only firm requirement is that it be run on an Intel-compatible system that is 286-equivalent or newer (386, 486, Pentium...). The 8086/ 8088 CPUs are no longer supported. See section 2.4, The PSEDIT Command Line and Switches, for instruction on how to start PSEDIT. Please look at the BackupMode= parameter of the PSEDIT.INI file to decide how you would like PSEDIT to handle backing up your file. You can specify that backups are never taken, that you are prompted to create a backup, or that backups are automatically made whenever a file is loaded. While never taking backups is very dangerous, always making backups is slower and can clutter up your disk with a bunch of backup files when all you wanted to do was view or print a file. The prompted mode is the default and most flexible. It only requires one extra keystroke each time a file is loaded. You may also specify what directory is to contain you backups. This can keep down the clutter somewhat. All backup files are named the same as the loaded file except with a .BAK extension. If you intend to modify a file with PSEDIT, I highly recommend making a backup file for obvious reasons. Since PSEDIT will allow you to change any file in any way, it is obviously a very dangerous weapon in the hands of the unskilled or careless as well as a very powerful tool in the hands of the skilled and careful. Please be careful! PSEDIT reads the entire file into virtual memory before any edits are performed. All changes are made only to the copy in memory until a SAVE is done. PSEDIT uses VMM, a virtual memory manager by Parity Solutions. VMM lets you utilize as much conventional, expanded and extended memory as you have, then overflows onto disk to simulate the remaining required memory. Assuming you have enough memory and disk space, you can edit files up to 64 megabytes in size. PSEDIT must have at least one byte in its data buffer to function, therefore, if you load a file with a length of 0, or delete all bytes in a file, one byte will show up on the screen and its value will be x00. PSEDIT has three different display modes and three different ways of selecting the one you prefer. The normal default mode is to display U.S. English characters and punctuation. The second adds international characters and the third adds graphics characters. If you wish to change the default, use the PSEDIT.INI file. If you want to change the initial mode for a single execution of PSEDIT, use the command line switches /I or /G as described under "Customizing PSEDIT." If you want to change the characters displayed after you have already loaded PSEDIT, use the ALT-I and ALT-G toggles as described below under "The Keyboard and Display." The reason the U.S. English letters and punctuation were selected as the default is first because most of the PSEDIT users are in the U.S., and second, because when most users refer to the ASCII portion, they are looking for a particular text string or phrase. Not displaying the graphics and international characters makes the phrase or word easier to spot. If you know exactly what you are looking for, use the search feature to locate it quickly. International users should not feel slighted, because you can easily change the default to display international characters. Unfortunately, you must display all international characters, not just the ones used in your language. 4.0 The Keyboard and Display The top line of the display shows the name, size, date and time of the file being edited. It also shows whether case-sensitivity is set on or off. There is also an area that will toggle between "HEX" and "ASCII" depending on which edit mode you are in. The upper-right corner contains two numbers in the format ddddddd:xhhhhhh. This is the current cursor location in both decimal (ddddddd) and hex (hhhhhh). The bottom line contains a quick reference of function keys and their usage. Other key functions can be displayed by pressing F1 (Help). Down the left side of the display is the offset from the start of the file to the first byte displayed on that line. The offset is in hex. HINT: The easy way to see where your cursor is currently located is to press ALT-D or ALT-H, rather than adding the horizontal offset to the offset on the left of the screen. The hex/decimal conversion windows will pop up with the current cursor location displayed in the operand field. ALT-D displays the offset in Decimal, ALT-H displays it in hex. There are two modes of editing in PSEDIT. When you first load a file, the screen appears with both hex data and its ASCII representation displayed in separate sections of the screen. The cursor is initially placed in the hex portion of the screen for editing in hex. The character (represented by two hex digits) at the cursor location appears red on color monitors. The same character on the ASCII (right) side will be light cyan. All other data characters are yellow. As the cursor moves, you will see the light cyan highlighting on the ASCII display move with the cursor and red letters of the hex display. Pressing TAB places the cursor in the ASCII portion and the display at the cursor becomes red. The corresponding position in the hex data becomes light cyan. TAB toggles the cursor back and forth between the two editing areas. The ASCII display does not display every displayable character, but only letters and numbers and the more common punctuation symbols that are common to most printers. All other characters appear as periods. You can only enter these characters on the ASCII side. To enter exotic characters you must use the hex representation on the hex side. If a blank appears on the ASCII display, it is because there is a true blank (hex 20) at that position. The following keys function as shown during editing: Page Down - Display the next page of data. Page Up - Display the previous page of data. Home - Position the cursor at the start of the file. End - Position the cursor at the end of the file. Down Arrow - Move the cursor down one line. Up Arrow - Move the cursor up one line. Right Arrow - Move the cursor right one byte. If at the end of a line, move to the first byte of next line. Left Arrow - Move the cursor left one byte. If at the start of a line, move to the last byte of the previous line. Enter - Same as right arrow. Tab - Swap the edit cursor between hex and ASCII modes. Back Tab - Clears the byte. You must then type something in the byte before the cursor can be moved. Insert - Insert one byte. Everything beyond this byte is shifted one position and a hex 00 byte is inserted at the cursor. Delete - Delete one byte at the cursor. Function keys: F1 - Display the help screen. F2 - Save any changes to the file on disk. F3 - Insert a specified number of bytes at cursor. F4 - Delete a specified number of bytes at cursor. F5 - Move the cursor to a specified address within the file. F6 - Print the file to LPT1:. It appears in basically the same format as displayed. F7 - Toggle case-sensitivity for ASCII string searches. F8 - Specify a search argument and locate the first occurrence of it in the file. F9 - Locate the next occurrence of the search argument. F10 - Display status of clipboard, blocked data and the virtual memory manager. Alt keys: ALT-C - Hex/decimal calculator ALT-D - Decimal to hex conversion ALT-H - Hex to Decimal conversion ALT-X - Exit PSEDIT. ALT-V - Toggle between 25-line and 43/50 line display modes. ALT-F6 - Print an address range. ALT-I - Toggle displaying of international characters. ALT-G - Toggle displaying of international and graphics characters. Block keys: CTL-K B - Mark the start of a block to be deleted. CTL-K K - Mark the end of a block to be deleted. CTL-K H - Unmark a currently marked block. CTL-K F - Fill a block with a given value. Clipboard function keys: CTL-INS - Copy blocked data to clipboard. CTL-DEL - Cut blocked data from the file and into the clipboard. SHFT-INS - Paste clipboard contents at current cursor location. The contents are inserted. Existing data is not overlaid. ESCAPE - Exit PSEDIT. 5.0 Modifying Data Modifying data is very simple, just type over it. Use the TAB key to select the hex or ASCII area. A MODE indicator on the top line will change to indicate whether you are in hex or ASCII edit mode. When typing in the hex area, only valid hex characters, 0-9 and A-F are allowed and upper case is forced. When entering data in the ASCII portion, only common printable characters are allowed and upper or lower case may be used. 5.1 Filling a block of data You may mark a block of data (see Deleting Data below) and then press CTL-K F. You will be prompted for a fill value (in HEX or ASCII depending on your edit mode) to overlay the contents of the blocked data. You may press ESCAPE at the prompt to abort the fill operation. Once you enter the value and press enter, the blocked area is filled with the value you specified. 6.0 Deleting Data First place the cursor on the first byte of the data that you want to delete. Pressing the DELETE key deletes one byte of data at this position. Press DELETE repeatedly to delete several bytes. If a large block needs to be deleted, press the F4 key and reply to the prompt with the number of bytes (up to the clipboard size as specified in PSEDIT.INI) you want to delete starting with the byte at the cursor. There is also a facility to mark a block and then delete it. Press CTL-K B to mark the first byte of a block, then press CTL-K K to mark the last byte of a block. Then press DELETE or F4 to delete the block. You can unmark a block by pressing CTL-K H. You can also change the start or end of the block at any time before the block is deleted or unmarked. These keys conform to WordStar-type conventions used in many text editors and word processors today. You can mark and delete blocks up to the size of the clipboard as specified in PSEDIT.INI. PSEDIT cannot handle a file with no data. If you delete all bytes in the file, PSEDIT will display a file with one byte of x00. 7.0 Inserting Data PSEDIT, rather than using an insert mode, lets you insert bytes of binary zeros, hex 00, into the file. You can then type over the inserted bytes with the data that you require, or you can use the fill function to fill the area with another value. Inserting data causes the file to grow. To allow for this growth, an additional 64k of virtual memory was acquired. Thus, if you insert more than 64 kilobytes, you must save the file and reload it to acquire another 64k expansion area. The size of the expansion area can be increased as high as 256k in the PSEDIT.INI file. Place the cursor at the byte where you want the data inserted. The data is inserted BEFORE the byte at the cursor. Pressing the INSERT key inserts one byte at a time. If a large block needs to be inserted, press F3 and specify the number of bytes you want inserted up to the size of the clipboard as specified in PSEDIT.INI. Once the null bytes appear, type over them if necessary. In order to add bytes to the end of the file, press END to go to the last byte of the file then press the right arrow. Each press of the right arrow adds a byte to the file. To enter a large block at the end of the file, press the right arrow once, then press F3 and specify the number of bytes needed less one (since you already added one when you pressed the right arrow). You can insert data from the clipboard by placing the cursor where you want the inserted data to begin and pressing SHIFT-INSERT. If the clipboard is empty, nothing will happen. Otherwise, the new data will appear inserted at the cursor location and marked as a block. This is so that if you made a mistake and placed it improperly, you can just press DELETE to delete it, reposition your cursor and hit SHIFT-INSERT again to reinsert it. Press CTL-K H to unmark the block. The data remains in the clipboard, so it can be inserted at multiple locations. 8.0 Using the Clipboard (Cut, Paste, Copy) PSEDIT contains a clipboard for use in cutting, pasting and copying marked blocks. It's size may range from 0 to 48k and is specified in PSEDIT.INI. The clipboard uses CUA keyboard conventions. First, mark a block of data (see Deleting Data for instructions on marking blocks), then press CTRL-INSERT to copy the block to the clipboard. Press SHIFT-DELETE if you want to copy the block to the clipboard and delete it from its current position in the file (Cut). Once you have cut or copied data into the clipboard, you may paste (insert) it anywhere in the file by using SHIFT-INSERT. See Inserting Data for details on using the paste feature. If you try to cut or copy a block that is greater than the clipboard size, a message window will pop up and the current block marks must be adjusted to select a smaller block. 9.0 Locating Data There are basically three ways to move the cursor to an area you want to edit. First you can use Page Down and Page Up to visually look for that area you want. Primitive, but effective. Second, if you know the offset into the program of the area you want to modify, press F5 and type the offset in hex. The third method is to let the computer search for a known byte config- uration. 9.1 Go to a Position in the File An offset or displacement is measured from the start of the file. The first byte is offset 0, the second is 1, etc. When you press F5, you are prompted for an offset which you provide in hex. The cursor is then placed at that address and display is updated to show the data at the cursor. This method is often used in applying documented patches supplied by a software vendor. 9.2 Search for Data Pressing F8 pops up a dialogue box that requests entry of a search argument. After supplying this argument, the cursor is positioned to the first occurrence of that value in the file. If it is not found, the cursor will appear on the last byte of the file. If a first occurrence is found, pressing F9 searches for the next occurrence. If a second is found, pressing F9 again searches for the third occurrence, and so on. If the cursor is in the hex editing area, you will be prompted for up to 30 hex bytes of search argument (60 hex digits). When the cursor is in the ASCII editing area, you may enter up to 60 ASCII characters for a search argument. Admittedly the search arguments are small, but I have found that when editing binary files, you are generally not looking for long strings. Hex data is normally entered in sets of two hex digits (nibbles) since it takes two hex digits to represent one byte. If you enter an odd number of hex digits, a zero nibble is prepended to the argument. For example, if you enter 18A, the resulting two bytes that are located are 01 8A. No byte swapping is ever done to accommodate the PC's low-high storage scheme of integer data. So if you are looking for an integer value of 1000 (decimal), hex 3E8, which is stored as hex E8 03, the search argument you would provide is E803. If you don't have a clue what this means, you probably don't need to be concerned about using PSEDIT in this manner. The F7 key is used to enable or disable case-sensitive searches when in ASCII character mode. The current state is shown on the top line of the display. If ON, upper/lower case letters must match exactly. If OFF, upper and lower case letters are equivalent. The CASE mode has no effect on hex mode searches. When searching in ASCII mode, and you want any number of trailing blanks in the search string, you must terminate the string with a double quote ("). If you want the last character to actually be a double quote, you must terminate the string with two double quotes (""). Example: ABC"" = [ABC"] ABC " = [ABC ] ABC = [ABC] In hex mode you specify trailing blanks with the hex characters 20. 9.3 Find and Replace Data ALT-F8 invokes the search/replace procedure. The search/replace procedure works much like the search procedure des- cribed above. Please read that section. In addition, you will be prompted to input a replace string. The rules for trailing blanks and quotes described above also apply to the replace string. When you proceed, each occurrence of the search string is located and you are prompted to see if you want to replace the instance of the search string at the current cursor location with the replace string you specified. If you reply Y, the contents are replaced and the next search string is sought, repeating this procedure until all instances of the search string have been found. You do not have to press F9. If you reply N to a replace prompt, the file is not modified and the next instance of the search string is sought. If you press ESC while the replace prompt is displayed, the search/ replace process is terminated. The initial window that prompts for the search and replace strings also contains a filed labeled "Prompt?". If you place a Y here, processing is as described above. If you place an N here, you are never prompted when an instance of the search string is located, and it is automatically replaced with the replace string. Every instance in the file is replaced. You will see the search strings as they are located, but they will pass quickly. 10.0 Print the File Printing the file is easy. You just press F6 and a window will pop up that tells you how many pages will be printed. You may abort at this time by pressing ESCAPE or replying N to the "Continue? (Y/N)" prompt. As pages are sent to the printer, the page number will be displayed. You may press any key to cancel printing at the end of the current page. The output is sent to standard print (PRN). The format is side-by-side hex/ASCII like that displayed on the screen with offset addresses (dis- placements) at the start of each line. 880 (hex 370) bytes are printed on each page. The pages are numbered and the file name, size, date and time appear at the beginning of each page. ALT-F6 allows you to supply a starting and ending address range to print. The actual pages printed will probably not start and end with the addresses you provided. Rather the pages (as if you had printed the entire file) that contain your starting address through your ending address will be the only pages printed. 11.0 Saving the File Prior to pressing F2 to save the file, all modifications are only done in virtual memory. F2 writes the file image in memory over the file that was originally loaded, and the changes become permanent. You may, however, change the file name at save time. A dialogue box will appear with the current file name. Accept it as is by pressing ENTER or modify it first. If the saved file name already exists you will be asked for verification before overwriting. 12.0 Hex/Decimal Conversions and Calculations Pressing ALT-D (Decimal-to-hex) pops up a window into which up to eight- digit decimal numbers can be entered. Pressing ENTER displays the results of converting this number to hexadecimal. Pressing ESC exits the window. Initially, the current cursor position is displayed in the operand field. Pressing ALT-H (Hex-to-Decimal) pops up a window into which up to eight- digit hexadecimal numbers can be entered. Pressing ENTER displays the results of converting this number to decimal. Pressing ESC exits the window. Initially, the current cursor position is displayed in the operand field. ALT-C pops up a hex/decimal calculator which will add, subtract, multiply or divide two hex, decimal or mixed values. The result is displayed in both\ hex and decimal. When entering the values to be calculated, precede hex values with an X (i.e. X31A0) and preceed decimal values with a D (i.e. D4095). Enter a plus (+) or minus (-) sign in the operator field. Press CTRL-ENTER when ready to calculate (or ENTER at the operator field). Since it is designed primarily to help you figure displacements within a program, the calculator operates on unsigned long (4-byte) integer values. Thus decimal points and negative numbers are not allowed. If you subtract a number from a smaller number, the result will be the 32-bit two's compliment of the negative result, usually a very high number. For instance, if you subtract 1 from 0, the result will be 4,294,967,295, the maximum for an unsigned long integer. If you compute a number with results higher than the above number, the results will be inaccurate. Let's hope you are not trying to edit any 4 Gb files! When you first invoke the calculator, the hex displacement of the current cursor location will be in the first operand. This facilitates calculating displacements forward or backward from the cursor. You can change the value to anything you like. HINT: The easy way to see where your cursor is currently located is to press ALT-D or ALT-H, rather than adding the horizontal offset to the offset on the left of the screen. The hex/decimal conversion windows will pop up with the current cursor location displayed in the operand field. ALT-D displays the offset in Decimal, ALT-H displays it in hex. 13.0 Exiting PSEDIT To quit PSEDIT, press ESC or ALT-X from the main edit screen. If your file has been modified since the last save, you will see a prompt: "Save file? (Y/N)". Pressing ESC again will return you to the point you were when you pressed ESC. A Y response invokes the save procedure then returns you to DOS or to the file name pick list if the editor was entered via the pick list. An N response bypasses the save procedure. To exit from the pick list screen to DOS, press ESC. Once you exit to DOS or the pick list, any unsaved modifications in the editor are lost. 14.0 Help Pressing F1 pops up a help screen describing the editing and function keys. Pressing ESCAPE (or any key when last page is displayed) removes the help window and returns you to the editor. Page Down and Page Up can be used to move between help pages. 15.0 A Useful Example - Modification of DOS 5's EDIT I prefer DOS 5's EDIT command by leaps and bounds over the EDLIN of previous DOSes, but there is one thing I especially don't like about it. When you select File/Open, it comes up with a default file list specification of *.TXT, like that is the only extension ever used for ASCII text files. I would prefer *.* and let me choose from all of my files. After reviewing all of the options, it appeared to me that there was no way to set this value to *.*. My next thought is that since there doesn't appear to be any type of configuration file for EDIT, the *.TXT string must be in the program, so I'll just pull out my trusty PSEDIT and zap it to *.*. Let's do it. Go to your directory where you keep DOS (usually C:\DOS). Type PSEDIT EDIT.COM. Since we know we are looking for an ASCII string of *.TXT, press TAB to swap the cursor to the ASCII area and press F8 to search. Enter *.TXT and press ENTER. You now find that your cursor is positioned on the last byte of the file. This means it didn't find the string we were looking for. Strange. But look! Right above our cursor are some messages that EDIT.COM displays. One of them reads, "Can not find file QBASIC.EXE." Oh yeah, I read somewhere that the EDIT editor with DOS 5 was a version of the QBASIC editor. Let's press ESCAPE, answer 'Y' and get back to the DOS prompt. Now let's enter PSEDIT QBASIC.EXE. Again let's go to the ASCII area with TAB and search for *.TXT with F8. Bingo! We found it. In my copy of DOS 5.0's QBASIC.EXE, I am now at a displacement of hex 3BCCA into the program and the cursor is positioned on the * of string *.TXT. Hit the right arrow twice to position the cursor on the first T. Type an asterisk (*). The string now shows *.*XT and the cursor is on the X. Lets change the X and T to hex 00s, which in most languages is used to terminate a string. Since we can't enter a binary zero field in the ASCII area, press TAB to switch the cursor back to the hex area. Now type four 0s. As you can see you have now changed the XT characters from hex 54 58 (the hex representation of X and T) to hex 00 00. This is what we wanted to do, so now let's save the file by pressing F2. Since the file was not backed up beforehand, type in a new file name (QBASIC.1) just to make sure it works before we destroy the original. Exit to DOS by pressing ESCAPE and Y. Rename the original to QBASIC.BAK and QBASIC.1 to QBASIC.EXE. Now type EDIT and go to the File/Open screen. Lo and behold! It now reads *.* and all of the files in the current directory are displayed in the pick list. You can go delete QBASIC.BAK now. APPENDIX A Installation PSEDIT is distributed in a self-extracting ZIP file called PSEDT.EXE. It contains the following files: PSEDIT.EXE The executable file for PSEDIT. PSEDIT.INI Configuration file for PSEDIT. PSEDIT.DOC The documentation file. PSEDIT.HST Modification descriptions for previous versions of PSEDIT. PSEDIT.Vnn Modification descriptions for current version nn. PRODUCTS.DOC A description of other Parity Solutions products available on CompuServe and ZiffNet. For best results, extract the file into a directory on your PATH. If you don't use a directory in your path, you will have to designate the directory containing PSEDIT.EXE when executing the program. If you have a utility directory that is on your PATH, this is an excellent location for PSEDIT. An example installation would be: C: CD \UTIL copy [path]PSEDT.EXE PSEDT DEL PSEDT.EXE If they are not currently in your path, simply copy all of the files to a directory in your path. Keep the PSEDT.EXE file anywhere you like, but give plenty of copies, as is, to your friends. If you register PSEDIT, you are not licensed to give your serial number to anybody without first removing the serialization from your copy. APPENDIX B Disclaimer BECAUSE OF THE DIVERSE NATURE OF COMPUTER EQUIPMENT AND EXPERTISE OF USERS, PARITY SOLUTIONS AND GARY C. CRIDER MAKE NO WARRANTY ON THE PSEDIT PROGRAM WHATSOEVER, EXPRESS OR IMPLIED. THE USER ASSUMES ALL RISK OF DAMAGE TO DATA OR EQUIPMENT RESULTING DIRECTLY OR INDIRECTLY FROM THE USE OR MISUSE OF THIS PROGRAM PRODUCT. THE USER MUST BE AWARE THAT USING PSEDIT TO MAKE ALTERATIONS TO PROGRAMS OR DATA CAN RENDER THAT PROGRAM OR DATA USELESS. USERS ARE ADVISED TO TEST MODIFICATIONS MADE WITH PSEDIT THOROUGHLY ON FILES FOR WHICH A BACKUP EXITS. ANY LIABILITY OF THE AUTHOR OR PARITY SOLUTIONS IS LIMITED TO REPLACEMENT OR REFUND OF THE REGISTRATION FEE. Any of the above disclaimers may not apply in your state if your state dis- allows such limits on product liability. APPENDIX C Support I have tried to test the program to the fullest, but I am limited as to systems and configurations with which to test. I have been programming for 18 years and the one thing I know for sure is that bug free programs are very few and far between. I can only promise to support the program to the best of my ability and provide fixes as expeditiously as possible. PSEDIT has been used at my home and work site extensively for several years and has proven to be a reliable tool. Anyone can report problems and suggest changes. Registered users get top priority in resolving their problems. There are three ways you can report problems. The preferred method is to contact me through CIS mail (not forum messages). My CIS ID is 71760,3413. You can also write me at: Gary C. Crider Parity Solutions 1903 Pavia Court Arlington, TX 76006 The last method is to phone (817) 261-9552. Since I am the sole technical support and the line is also used for my network consulting business, it is often hard to get through to me. Please call and leave a message between 7:30 am and 5:30 pm Central time. No matter which method you use, please give a brief description of your problem, the release number of your program, your registration serial number if you are registered, and your phone number. If I need more information, I will contact you as soon as I can. When I have a solution, I will contact you however you prefer. I work full time, have a consulting business to run in my spare time and write programs instead of sleeping. So please be a little patient with me. Program updates are available on CompuServe or can be requested from us for a $5 shipping and handling charge. Add $1 for international shipping outside the U.S., Canada and Mexico. A distribution disk of all Parity Solutions products will be sent to you. Specify disk size and format. APPENDIX D Registration I begin with an apology. I hate programs that in any way inhibit func- tionality or performance for the shareware version. But when it came down to feeding the family and paying the bills, I had a change of heart and inserted a pesky notice that pops up at the beginning and gets on your nerves. I chose this approach above that of limited functionality. The program's full capabilities are available for you to evaluate before you invest your hard- earned money. Registered users will receive a unique serial number and instructions on how to serialize the program. Serialization can be re-applied to updated versions and in no way hinders your use of the program. You can compress or decompress the program with no effect. It is already compressed before distribution. As a registered user, you will be able to update without re-registration or additional fees. To register your copy, please send $24 US ($95 per file server on LANs) check or money order (sorry, no credit cards yet) to: Gary C. Crider Parity Solutions 1903 Pavia Court Arlington, TX 76006 Purchase orders for amounts of $72 or more are accepted from U.S. or Canadian companies and institutions. Add $1 to total order for postage outside the U.S., Canada and Mexico. Or, you can register single-use licenses online quickly and easily in Compuserve. Simply GO SWREG and register ID #751. Your registration will be added to your Compuserve bill. International exchange was never easier, and you save the $1 postage charge. If you send your CIS ID or register via SWREG, your registration will be sent to you via CIS mail, along with instructions on how to serialize your copy of PSEDIT. This usually involves one day or less turnaround. Program diskettes are not normally shipped. Normal distribution is via CompuServe. If you need a diskette, please see the instructions under Support above. You will receive a serial number and instructions for serializing your copy of the program. Each license gives you or your company a single use permit for PSEDIT. It is not restricted to a single machine as long as no two users can be simul- taneously using the program. As Borland says, "treat it like a book." As an example, if you register PSEDIT for your home computer, but during the day you use a portable or a computer at work, you may keep PSEDIT on both machines as long as no one is at home using it on your home computer. LAN licenses grant rights to all users of a file server. If inter- networking, a license must exist for each file server that contains a copy of PSEDIT.EXE. If two or more file servers exist on a single LAN strictly for mirroring data and fault-tolerance, these will be counted as a single file server for licensing purposes. If in doubt, contact me. We can work out an agreement. Site licensing is also available on a negotiated price basis. I guarantee it will be an economical alternative to buying licenses for each user. You may freely distribute the original PSEDT.EXE file in any way you see fit other than selling it. Users' groups and shareware distribution services may charge a reasonable fee for the medium and duplication costs. Bulletin boards may not charge additional fees for downloading this specific program, other than normal connect-time and/or membership charges. You are NOT licensed to give anyone your serial number unless you first remove all serialization from your computer. You may then no longer use that serial number. Only Parity Solutions has the authority to issue serial numbers. Modification of PSEDIT.EXE in any way is prohibited and unlawful. Licensees of Parity Solutions' BEDIT program may serialize PSEDIT by renaming BEDIT.SER to PSEDIT.SER. ============================================================================== ORDER FORM FOR PSEDIT Send checks payable to: Parity Solutions 1903 Pavia Court Arlington, TX 76006 BILLING ADDRESS: SHIP TO (If different): NAME: _____________________________ NAME: ___________________________ COMPANY: _____________________________ COMPANY: _____________________________ STREET: _____________________________ STREET: _____________________________ _____________________________ _____________________________ CITY/ST: _____________________________ CITY/ST: _____________________________ ZIP/POSTAL CODE: _____________________ ZIP/POSTAL CODE: _____________________ COUNTRY: _____________________________ COUNTRY: _____________________________ PHONE: _____________________________ PHONE: _____________________________ CompuServe ID: _______________________(Optional) NOTE: Parity Solutions sends a serial number for each registration and instructions for serializing your program. A diskette containing the latest releases of all Parity Solutions shareware products is available for $5.00 U.S. The current release of PSEDIT is avail- able for downloading on CompuServe in the IBMSYS forum. QTY DESCRIPTION PRICE EA. TOTAL PRICE ___ PSEDIT license and registration $24.00 ___________ ___ PSEDIT Network license and registration 95.00 ___________ ___ Parity Solutions shareware diskette 5.00 ___________ International postage outside U.S., 1.00 ___________ Canada and Mexico. Total Enclosed: ___________ Diskette size (if ordered): __ 5.25" 360k __ 5.25" 1.2M __ 3.5" 760k Thank you for doing business with Parity Solutions. (817) 261-9552 Parity Solutions is a partnership of Gary C. Crider and Russell L. McCloud. Federal tax identification number 75-2468376. ==============================================================================