HW: Run a function from a separate file on a pthread?

Question

I have code that makes a bunch of threads, and assigns them a function.

file a.c:
#include "b.h"
int main()
{
    pthread_t tids[n];
    void * (*func) (void*);
    func = function_thread; \\this is the process from another function
    //more code
    for(int i = 0; i < n; i++){
        pthread_create(&tids[i], NULL, func, (void*)i));
    }
}

file b.c:
void * function_thread(void * i)
{
    //do stuff
    pthread_exit(NULL);
}

Is there anything special I need to do to make this work?

I ask, because right now I'm getting something like the following when I try to make this. Am I on the right track, or is this error caused by something else entirely?

/tmp/ccAiAxMg.o: In function `main':
a.c:(.text+0x4f8): undefined reference to `function_thread'

I know the b.h file is linked just fine, because I'm using structs in it without any complaints from the compiler.

How are you building? Because right now you don't seem to be building both source files. — Some programmer dude, Mar 08 '15 at 07:49
I'm using a make file the line is `a: ./a.c ./libutil.a $(CC) $(CFLAGS) -o $@ ./a.c -L$(UTILDIR) $(UTILFLAG)` — Derek Halden, Mar 08 '15 at 07:58
And where do you build and link the `b.c` ***source*** file? — Some programmer dude, Mar 08 '15 at 07:58
utildir, and utilflag both have to do with the libutil.a file, I mention there. — Derek Halden, Mar 08 '15 at 07:59
Okay, then can you show the complete build output from the makefile? It will tell us exactly what commands are run, and what files and flags are used. And preferably the actual makefile as well? — Some programmer dude, Mar 08 '15 at 08:00
Although tagged C++ only, this might help: http://stackoverflow.com/q/12573816/694576 — alk, Mar 08 '15 at 08:35

HW: Run a function from a separate file on a pthread?

0 Answers0