NAME |LIBRARY |SYNOPSIS |DESCRIPTION |RETURN VALUE |ERRORS |STANDARDS |HISTORY |SEE ALSO |COLOPHON | |
getresuid(2) System Calls Manualgetresuid(2)getresuid, getresgid - get real, effective, and saved user/group IDs
Standard C library (libc,-lc)
#define _GNU_SOURCE/* See feature_test_macros(7) */#include <unistd.h>int getresuid(uid_t *ruid, uid_t *euid, uid_t *suid);int getresgid(gid_t *rgid, gid_t *egid, gid_t *sgid);
getresuid() returns the real UID, the effective UID, and the saved set-user-ID of the calling process, in the argumentsruid,euid, andsuid, respectively.getresgid() performs the analogous task for the process's group IDs.
On success, zero is returned. On error, -1 is returned, anderrno is set to indicate the error.
EFAULTOne of the arguments specified an address outside the calling program's address space.
None. These calls also appear on HP-UX and some of the BSDs.
Linux 2.1.44, glibc 2.3.2. The original Linuxgetresuid() andgetresgid() system calls supported only 16-bit user and group IDs. Subsequently, Linux 2.4 addedgetresuid32() andgetresgid32(), supporting 32-bit IDs. The glibcgetresuid() andgetresgid() wrapper functions transparently deal with the variations across kernel versions.
getuid(2),setresuid(2),setreuid(2),setuid(2),credentials(7)
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