Thread: Working with multiple source files

I have a similar question so I thought I would necro this thread.

I'm a math student trying to write a program so I don't know too much. I'm working on fedora code 5.
I am trying to make a call to a C program called nauty (it calculates automorphism groups of graphs).
As a first step I'm just trying to run one of it's example programs, which executes a simple call to nauty.
However it says "It needs to be linked with nauty.c nautil.c and naugraph.c.".
I've got a vague idea of what that means from reading around here a little bit.
When I try to compile my example program I get a whole host of errors. It seems that the example cannot find nauty. This isn't too suprising since nauty is in a different folder.

So my question is: how do I link my example program to other c files that are located elsewhere?

Here is the example program in full.
The nauty files are in /usr/local/nauty22

Code:

/* This program prints generators for the automorphism group of an
   n-vertex polygon, where n is a number supplied by the user.
   It needs to be linked with nauty.c, nautil.c and naugraph.c.
   This version uses a fixed limit for MAXN.
*/
#define MAXN 100
#include "nauty.h"   /* which includes <stdio.h> */
main()
{
    graph g[MAXN*MAXM];
    int lab[MAXN],ptn[MAXN],orbits[MAXN];
    static DEFAULTOPTIONS(options);
    statsblk(stats);
    setword workspace[50*MAXM];
    int n,m,v;
    set *gv;
    options.writeautoms = TRUE;
    while (1)
    {
        printf("\nenter n : ");
        if (scanf("%d",&n) == 1 && n > 0)
        {
            if (n > MAXN)
            {
                printf("n must be in the range 1..%d\n",MAXN);
                exit(1);
            }
            m = (n + WORDSIZE - 1) / WORDSIZE;
            nauty_check(WORDSIZE,m,n,NAUTYVERSIONID);
            for (v = 0; v < n; ++v)
            {
                gv = GRAPHROW(g,v,m);
                EMPTYSET(gv,m);
                ADDELEMENT(gv,(v+n-1)%n);
                ADDELEMENT(gv,(v+1)%n);
            }
            printf("Generators for Aut(C[%d]):\n",n);
            nauty(g,lab,ptn,NULL,orbits,&options,&stats,
                                            workspace,50*MAXM,m,n,NULL);
        }
        else
            break;
    }
}

Hopefully I havn't broken any protocal here.
Thanks very much for any and all advice.

You would type "gcc" followed by all the .c files needed to make a complete program. If they are in different directories, you can specify a path to those files, or move all the .c files so they are together.

Thanks very much, I appreaciate it ^^