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TonyLB · Posted: Mon Apr 17, 2006 5:19 pm Post subject: C functions and libraries

I'm just learning C as another language, and I'm trying to build some utilities into a library. I have this (crude I know) function:
void insert(char* insrt, char* source, int place){
char temp[strlen(insrt)+strlen(source)+1];
strncpy(temp, source, place);
temp[place]='\0';
strcat(temp, insrt);
strcat(temp, source+place);
strcpy(source, temp);
}

In a simple file, it all works, but in a static library, when I call it I get a segnmentation fault. The villain is the final strcpy.

I tried returning temp instead and that doesn't work either, I don't get quite the string that exists in the function (and the compiler warns about returning a local variable).

I know there's a solution, I just have no idea what it is. Any help would be great.

Tony

Nigel · Posted: Tue Apr 18, 2006 9:33 am Post subject: RE: C functions and libraries

OK, I think the answer lies in how you are calling the routine. Are you doing something like this...

TonyLB · Posted: Wed Apr 19, 2006 6:07 pm Post subject: RE: C functions and libraries

Thanks, yes.
In fact, in my original code I'd uses a char array which was passed to insert, and the later version user a char* instead, which seems to be the problem at least in part since there was no room for the inserted characters.

Tony
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