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- SUBMISSION
- by Editor, Ann Arbor KUG, May 1987
-
- (Some interesting notes on SUBMIT)
-
- SUBMIT, the CP/M batch processor, can do some things that Digital
- Research never told you about.
-
- Just about everyone knows that SUBMIT will treat lines in the SUB
- file that begin with a semicolon (or one of a handful of other
- characters) as comments; but did you know that there is a better
- way to comment your more obscure SUB files?
-
- Normally, blank lines in a SUB file are a no-no. SUBMIT will
- choke when it comes across a blank line, even if it occurs at the
- end of the file. Well, it turns out that you can make use of
- this little "bug"!
-
- Actually, you can place whatever text that you wish at the
- beginning of you SUB file. (There is an absolute limit on the
- amount, but you are not likely to reach it unless you get very
- wordy. SUBMIT will let you know and not do anything drastic.).
- No semicolons or other nonsense is necessary. This is a good
- place to put a description of exactly what the SUB file does --
- in plain English. The trick is to place a blank line right
- before the actual commands, and everything will work beautifully!
-
- This trick will NOT work with EX, GSUB, SuperSUB or other batch
- processors. If you have used some of these other programs, you
- are probably wondering why anyone would want to use SUBMIT in the
- first place. Well, SUBMIT is useful for loading memory resident
- programs (like LBRDISK and some of the keyboard enhancers) that
- locate themselves just below the CCP. You just can't do this
- with EX and GSUB because they occupy the same space.
-
- For the technically curious: All SUBMIT really does is create
- the file "$$$.SUB" on drive A. When SUBMIT creates this file, it
- loads the commands in your file from the bottom up. Thus, when
- it reaches the blank line that separates your opening text from
- the commands, it stops (chokes). An error does not occur,
- however, and SUBMIT expires quietly with a warm boot. At this
- point the CCP begins execution of the "$$$.SUB" file, working
- from the bottom (where your first command is) upward. In this
- way, the temporary "$$$.SUB" is eroded until it is erased from
- the directory after the last command.
-
- If you wish to look at the "$$$.SUB" file you will have to be
- clever. Since the file is created on drive A:, and the CCP will
- always execute it if possible after a warm or cold boot, this
- file can be elusive. If you press reset during the execution of
- the file, the darned thing will just start up where it left off
- when CP/M comes back. Also, if you do manage to capture the file
- (by copying it during the execution or some other trick) you will
- find that it seems to contain only one command -- the last one,
- and perhaps the remnants of some previous command. Look at the
- file with CCT or some other program that will give you a hex and
- ASCII dump of the whole file. You may find it interesting.