#include <sys/types.h>
#include <sys/wait.h>
#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <pwd.h>

int main(int ac, char *av[])
{
    pid_t childPid;
    const char *userName = "gismobile";

    if((childPid = fork()) == 0)
    {
        /*
         * If a user name is specified, try to set our uid to match that
         * user name.  This is to allow e.g. a banner page to show the
         * name of the printing user rather than the user who started
         * the print server.
         */
        if(userName)
        {
            uid_t myUid;

            if((myUid = geteuid()) == (uid_t)0)
            {
                struct passwd *pPasswd;

                if((pPasswd = getpwnam(userName)))
                {
                    setgid((gid_t)pPasswd->pw_gid);
                    if( initgroups(userName, (gid_t)pPasswd->pw_gid) != 0 )
                    {
                      perror("initgroups failure");
                    }

                    printf("child: Setting uid=%d\n", (int)pPasswd->pw_uid);
                    setuid((uid_t)pPasswd->pw_uid);
                    system("/usr/bin/id");
                }
                else
                {
                    printf("child: getpwnam() failed\n");                    
                }
            }
        }
        fork();
        /* return BadAlloc? */
        if (execv("/usr/bin/id", NULL) == -1) {
            fprintf(stderr, "child: unable to exec '%s'\n", "/usr/bin/id");
        }
    }
    else
    {
        int status;

        (void) waitpid(childPid, &status, 0);
    }

    return EXIT_SUCCESS;
}