brief program to simulate how nullmailer-queue opens adminaddr file

readfile.c (text/x-csrc), 456 bytes, created by Michael Yagliyan on 2022-12-29 17:28:04 UTC

#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>

int main(int ac, char ** av)
{
    printf("UID = %d, EUID = %d\n"
           "GID = %d, EGID = %d\n",
           getuid(),
           geteuid(),
           getgid(),
           getegid());
    int rc = openat(AT_FDCWD, "/etc/nullmailer/adminaddr", O_RDONLY);
    printf("openat returned %d, errno is %d (%s)\n", rc, errno, strerror(errno));

    return 0;
}