Shareware Grab Bag/Shareware Grab Bag.iso/007/a86a.arc/INVOKE.DOC

Text File | 1986-06-22 | 5.6 KB | 104 lines

---INVOKE.DOC---

A86 Program Invocation

To invoke A86, you must provide a program invocation line, either typed to the
console when the DOS command prompt appears, or included in a batch file.  The
program invocation line consists of the following:

1. The program name A86.

2. The names of the source files you want to assemble.  You may use the wild-
   card delimiters * and ? if you wish, to denote a group of source files to be
   assembled.  A86 will sort all matching names into alphabetical order for
   each wild-card specification; so the files will be assembled in the same
   order even if they get jumbled up within a directory.

   A86 identifies the end of the source file names when it sees a name with no
   extension, or a name with the default object-extension.  That extension is
   .COM, unless you have assembled an ORG 0 statement; in which case the default
   extension is .OBJ. Sorry, you cannot have a source file with the default
   object extension.

3. You may optionally provide the word TO, to separate the source file names
   from the output file names.

4. The name of the output program.  If you do not provide an extension, A86
   will assume that you want the extension .COM (.OBJ if you had an ORG 0).
   If you want your program file to have no extension, you end the file name
   with a period.

   You have the option to omit both the program file name and the symbol table
   file name from the invocation.  If you do so, A86 will output the program
   source.COM (or source.OBJ) and the symbol table source.SYM; where "source"
   is a name derived from the list of source files, according to the rules
   described in the section "Strategies for Source File Maintenance" below.

5. The name of the symbol-table file.  If you do not provide an extension, A86
   will assume that you want the extension .SYM.  If you want your symbol table
   file to have no extension, you end the file name with a period.

   You have the option to omit the name of the symbol table file.  If you do
   so, A86 will use the same root as the output program name, with a .SYM
   extension.  If you desire no symbol table file, specify "NUL.".  Be sure to
   put a period after NUL, or else you will get a file called NUL.SYM.  (NUL is
   the DOS "garbage can" device, which discards anything output to it.)


Strategies for Source File Maintenance

A86 encourages modular programming, by letting you break your source into
separate files, with complete impunity.  A86 has no concern whatsoever for
file breaks-- it treats the sequence of files as a single source code stream.

You should build up libraries of source modules, containing commonly-used
procedures.  Whenever you need the functionality of a procedure, you can simply
include the appropriate source file in the list of files to be assembled.

You should consider one or more of the following strategies, which I have
adopted in my source file management:

1. I name all my A86 source files with the same extension, which is found on
   no other files. The particular extension I have chosen is ".8". I did not
   choose the more common .ASM; because I have a few source-files designed for
   MSDOS's assembler.  If you don't like .8, I would suggest .A86.

2. I keep a separate sub-directory on my hard disk for each multi-source-file
   A86 program I have.  Then the simple command "A86 *.8" performs the assembly
   for the current directory's program.

3. I exploit the fact that A86 expands wild-cards into alphabetical order.
   Whenever I want a source-file to be assembled first (e.g., when it contains
   variable declarations), I append a decimal digit to the start of the file
   name: 0 for the first file, 1 for the second, etc., for however many files
   that need to be explicitly ordered.  If a file needs to come last, I append
   a "Z" to the start of the file name.

   To accomodate the above strategy, I have programmed A86 to a somewhat
   complicated algorithm for determining the default output file-name.  I use
   the name of the first source file; but I truncate the first character if
   it is a decimal digit.  However, you may have a library file that must come
   first; so I have provided the following exception: if you have a source-file
   whose name begins with the digit "9", that name (without the 9) is used.
   If you don't like this, you can always explicitly give the program name you
   want: "A86 *.8 MYPROG".

4. If I have a source file used in more than one program, I do not want to have
   more than one copy of that program exist on the disk for any amount of time.
   There is a reason for this that is much more important than wasted space:
   I wish any bug-fixes or enhancements to those files to be propagated to all
   programs using those files.  I wish no confusion as to precisly which copy
   is the latest version.

   There are two ways to accomplish the above-stated goal of one-copy-per-file.
   First, I can make a .BAT file for assembling each program, that explicitly
   lists the source files for that program, wherever they may be.  Or second,
   I can make files GET.BAT and DEL.BAT.  GET.BAT temporarily copies the common
   files from a library-directory into the program's directory.  I work on the
   program; then when I am finished, DEL.BAT deletes the files, as well as
   *.BAK, *.SYM, *.ERR, and *.OLD; leaving a clean directory.  If you wish to
   have the option of modifying the library files, then you should have DEL.BAT
   copy those files back to the library directories, before deleting them from
   the local directory.