Originální popis anglicky:
seteuid, setegid - set effective user or group ID
Návod, kniha: Linux Programmer's Manual
#include <sys/types.h>
#include <unistd.h>
int seteuid(uid_t euid);
int setegid(gid_t egid);
seteuid sets the effective user ID of the current process. Unprivileged
user processes may only set the effective user ID to the real user ID, the
effective user ID or the saved user ID.
Precisely the same holds for
setegid with "group" instead of
"user".
On success, zero is returned. On error, -1 is returned, and
errno is set
appropriately.
- EPERM
- The current process is not privileged (Linux: does not have
the CAP_SETUID capability in the case of seteuid(), or the
CAP_SETGID capability in the case of setegid()) and
euid (resp. egid) is not the real user (group) ID, the
effective user (group) ID or the saved user (group) ID.
Setting the effective user (group) ID to the saved user (group) ID is possible
since Linux 1.1.37 (1.1.38). On an arbitrary system one should check
_POSIX_SAVED_IDS.
Under libc4, libc5 and glibc2.0
seteuid(euid) is equivalent
to
setreuid(-1, euid) and hence may change the saved user
ID. Under glibc2.1 it is equivalent to
setresuid(-1,
euid,-1) and hence does not change the saved user ID. Similar
remarks hold for
setegid.
BSD 4.3
geteuid(2),
setresuid(2),
setreuid(2),
setuid(2),
capabilities(7)
