getresgid, getresuid, setresgid, setresuid - get or set real, effective
and saved user or group ID
getresgid(gid_t *rgid, gid_t *egid, gid_t *sgid);
getresuid(uid_t *ruid, uid_t *euid, uid_t *suid);
setresgid(gid_t rgid, gid_t egid, gid_t sgid);
setresuid(uid_t ruid, uid_t euid, uid_t suid);
The setresuid() function sets the real, effective and saved
user IDs of
the current process. The analogous setresgid() sets the real, effective
and saved group IDs.
Privileged processes may set these IDs to arbitrary values.
processes are restricted in that each of the new IDs must
match one of
the current IDs.
Passing -1 as an argument causes the corresponding value to
The getresgid() and getresuid() calls retrieve the real, effective, and
saved group and user IDs of the current process, respectively.
Upon success, these functions return 0; otherwise -1 is returned.
[EPERM] The calling process was not privileged and
tried to change
one or more IDs to a value which was not the
ID, the current effective ID nor the current
[EFAULT] An address passed to getresgid() or
getresuid() was invalid.
getegid(2), geteuid(2), getgid(2), getuid(2), issetugid(2),
setregid(2), setreuid(2), setuid(2)
These functions are not part of the IEEE Std 1003.1
and should not be used where portability is desired.
These functions first appeared in HP-UX.
OpenBSD 3.6 October 20, 2002
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