From:	Shaun Jackman <sjackman AT rogers DOT wave DOT ca>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Modify global variables from within a program
Date:	Sun, 15 Feb 1998 19:44:02 -0800
Organization:	ARC Technologies
Lines:	48
Message-ID:	<34E7B601.DAE03C63@rogers.wave.ca>
NNTP-Posting-Host:	pc-15794.bc.rogers.wave.ca
Mime-Version:	1.0
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

I want to be able to modify global variables from within the program I
am writing, through a console interface.
To implement this I wrote a little script:
nm *.o|sort|uniq|grep 00000004|tail -n +2|tr \040 \t|cut -f 3>out1
paste -d \"\" NUL out1 NUL>out2
paste -d (&,); register NUL out1 out2 NUL NUL|uniq>globals
echo void register_globals() {>globals.c
cat globals>>globals.c
echo }>>globals.c

(note: the file "register" is simply a file containing 100 lines of
"register_global")

This scans all the *.o files in the current directory, extracts the
global variables, and writes a c file called globals.c
For example, if there were a bunch of some source files that declared
int globalvar1;
int globalvar2;
int globalvar3;

Then my script would write a c file:
void register_globals() {
  register_global(&globalvar1, "globalvar1");
  register_global(&globalvar2, "globalvar2");
  register_global(&globalvar3, "globalvar3");
}

which I could then compile and link into the program.
(assuming there is a function called register_global that hashes the
string and links it to the variable, to make it available for the
console)

Unfortuneately, I haven't been using the unix textutils very long, and
I'm not quite sure how to use them properly.
What this script actually gives is:
void register_globals() {
  register_global(&_globalvar1, "_globalvar1");
  register_global(&_globalvar2, "_globalvar2");
  register_global(&_globalvar3, "_globalvar3");
  register_global(&,);
}

How can I fix my script?
Or, is there a better way to do what I'm doing?

Thanks for your help,
Please reply by e-mail as well if possible,
Shaun Jackman

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