> From: Alex Vinokur
> Sent: Monday, November 03, 2003 6:05 AM
> Executable files contain various printable information.
> For instance, list of used DLLs.
>
> However those files contain neither compiler name nor compiler version.
> It seems to be worth including something like "gcc version 3.3.1
> (cygming special)" in executables.
>
> Next question. Is it possible to add 'user related printable
> information' to executables (through compilation option or something
> else)?
The answer depends on how you plan to use that information.
The simplest form is just to declare a static string (char array), making
sure that the compiler doesn't remove it at optimization. (Hmm...? Is it
enough to do some dummy reference to it?)
This gives a simplified image of the true heuristics but anyway;
on the old AmigaOS they use(d) something like:
$ cat chk.c
int main() {
char versionstring[]="$VER: name major.minor (date) extended_info";
return 0;
}
$ for (( n=0; n<4; n++ )) do
gcc -O$n chk.c;
echo -n $n:;
strings a.exe | grep '$VER: ';
done
0:$VER: name major.minor (date) extended_info
1:$VER: name major.minor (date) extended_info
2:$VER: name major.minor (date) extended_info
3:$VER: name major.minor (date) extended_info
Hmm... :-} it doesn't get removed by plain optimization... :-)
/Hannu E K Nevalainen, B.Sc. EE - 59?16.37'N, 17?12.60'E
-- printf("LocalTime: UTC+%02d\n",(DST)? 2:1); --
--END OF MESSAGE--
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