posix - Example of realpath function in C

Question

I'm looking for an example of how to use the realpath function in a C program. I can't seem to find one on the web or in any of my C programming books.

Answer 1

The realpath() function is not described in the C Standard. It is however described by POSIX 1997 and POSIX 2008. If that is what you mean, here is an example:

#include <limits.h> /* PATH_MAX */
#include <stdio.h>
#include <stdlib.h>
int main(void) {
    char buf[PATH_MAX]; /* PATH_MAX incudes the  so +1 is not required */
    char *res = realpath("this_source.c", buf);
    if (res) {
        printf("This source is at %s.
", buf);
    } else {
        perror("realpath");
        exit(EXIT_FAILURE);
    }
    return 0;
}

PATH_MAX is defined in <limits.h> (<limits.h> from POSIX 1997)