Files
oldlinux-files/study/linux-travel/MINIX-1.5/1.5/Source/commands/id.c
2024-02-19 00:25:23 -05:00

53 lines
1.3 KiB
C

/* id - return uid and gid Author: John J. Marco */
/*=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-*/
/* ----- id.c ----- */
/* Id - get real and effective user id and group id */
/* Author: John J. Marco */
/* pa1343@sdcc15.ucsd.edu */
/*-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=*/
#include <sys/types.h>
#include <pwd.h>
#include <grp.h>
#include <stdio.h>
main()
{
struct passwd *pwd;
struct passwd *getpwuid();
struct group *grp;
struct group *getgrgid();
int uid, gid, euid, egid;
uid = getuid();
gid = getgid();
euid = geteuid();
egid = getegid();
if ((pwd = getpwuid(uid)) == (struct passwd *) NULL)
printf("%s%d%s", "uid=", uid, " ");
else
printf("%s%d%s%s%s", "uid=", uid, "(", pwd->pw_name, ") ");
if ((grp = getgrgid(gid)) == (struct group *) NULL)
printf("%s%d%s", "gid=", gid, " ");
else
printf("%s%d%s%s%s", "gid=", gid, "(", grp->gr_name, ") ");
if (uid != euid)
if ((pwd = getpwuid(euid)) != (struct passwd *) NULL)
printf("%s%d%s%s%s", "euid=", euid, "(", pwd->pw_name, ") ");
else
printf("%s%d%s", "euid=", euid, " ");
if (gid != egid)
if ((grp = getgrgid(egid)) != (struct group *) NULL)
printf("%s%d%s%s%s", "egid=", egid, "(", grp->gr_name, ") ");
else
printf("%s%d%s", "egid=", egid, " ");
printf("\n");
}