1 /* id.c - print real and effective user and group IDs
3 * Copyright 2012 Sony Network Entertainment, Inc.
5 * by Tim Bird <tim.bird@am.sony.com>
7 * See http://opengroup.org/onlinepubs/9699919799/utilities/id.html
9 USE_ID(NEWTOY(id, "nGgru", TOYFLAG_BIN))
17 Print user and group ID.
19 -n print names instead of numeric IDs (to be used with -Ggu)
20 -G Show only the group IDs
21 -g Show only the effective group ID
22 -r Show real ID instead of effective ID
23 -u Show only the effective user ID
29 static void s_or_u(char *s, unsigned u, int done)
31 if (toys.optflags & FLAG_n) printf("%s", s);
39 static void showid(char *header, unsigned u, char *s)
41 printf("%s%u(%s)", header, u, s);
44 struct passwd *xgetpwuid(uid_t uid)
46 struct passwd *pwd = getpwuid(uid);
47 if (!pwd) error_exit(NULL);
51 struct group *xgetgrgid(gid_t gid)
53 struct group *group = getgrgid(gid);
54 if (!group) error_exit(NULL);
60 int flags = toys.optflags, i, ngroups;
63 uid_t uid = getuid(), euid = geteuid();
64 gid_t gid = getgid(), egid = getegid(), *groups;
66 // check if a username is given
68 if (!(pw = getpwnam(*toys.optargs)))
69 error_exit("no such user '%s'", *toys.optargs);
70 uid = euid = pw->pw_uid;
71 gid = egid = pw->pw_gid;
74 i = toys.optflags & FLAG_r;
75 pw = xgetpwuid(i ? uid : euid);
76 if (flags & FLAG_u) s_or_u(pw->pw_name, pw->pw_uid, 1);
78 grp = xgetgrgid(i ? gid : egid);
79 if (flags & FLAG_g) s_or_u(grp->gr_name, grp->gr_gid, 1);
81 if (!(flags & FLAG_G)) {
82 showid("uid=", pw->pw_uid, pw->pw_name);
83 showid(" gid=", grp->gr_gid, grp->gr_name);
88 showid(" euid=", pw->pw_uid, pw->pw_name);
91 grp = xgetgrgid(egid);
92 showid(" egid=", grp->gr_gid, grp->gr_name);
96 showid(" groups=", grp->gr_gid, grp->gr_name);
99 groups = (gid_t *)toybuf;
100 if (0 >= (ngroups = getgroups(sizeof(toybuf)/sizeof(gid_t), groups)))
103 for (i = 0; i < ngroups; i++) {
105 if (!(grp = getgrgid(groups[i]))) perror_msg(0);
106 else if (flags & FLAG_G) s_or_u(grp->gr_name, grp->gr_gid, 0);
107 else if (grp->gr_gid != egid) showid("", grp->gr_gid, grp->gr_name);