Originální popis anglicky:
setresuid, setresgid - set real, effective and saved user or group ID
Návod, kniha: Linux Programmer's Manual
#define _GNU_SOURCE
#include <unistd.h>
int setresuid(uid_t ruid, uid_t euid, uid_t
suid);
int setresgid(gid_t rgid, gid_t egid, gid_t
sgid);
setresuid sets the real user ID, the effective user ID, and the saved
(effective) user ID of the current process.
Unprivileged user processes (i.e., processes with each of real, effective and
saved user ID nonzero) may change the real, effective and saved user ID, each
to one of: the current uid, the current effective uid or the current saved
uid.
The super-user may set real, effective and saved user ID to arbitrary values.
If one of the parameters equals -1, the corresponding value is not changed.
Completely analogously,
setresgid sets the real, effective and saved
group ID's of the current process, with the same restrictions for processes
with each of real, effective and saved user ID nonzero.
On success, zero is returned. On error, -1 is returned, and
errno is set
appropriately.
- EAGAIN
- uid does not match the current uid and this call
would bring that userID over its NPROC rlimit.
- EPERM
- The current process was not privileged (did not have the
CAP_SETUID capability) and tried to change the IDs is a not allowed
way.
This call is nonstandard.
This system call was first introduced in HP-UX. It is available under Linux
since Linux 2.1.44. These days it is also found in FreeBSD (for emulation of
Linux binaries).
Under HP-UX and FreeBSD the prototype is found in
<unistd.h>. Under
Linux the prototype is given by glibc since version 2.3.2 provided _GNU_SOURCE
is defined.
getresuid(2),
getuid(2),
setreuid(2),
setuid(2),
capabilities(7)
