getresuid

GETRESUID(2)                Linux Programmer's Manual               GETRESUID(2)



NAME
       getresuid, getresgid - get real, effective, and saved user/group IDs

SYNOPSIS
       #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);

DESCRIPTION
       getresuid() returns the real UID, the effective UID, and the saved set-
       user-ID of the calling process, in the arguments ruid, euid, and suid,
       respectively.  getresgid() performs the analogous task for the process's
       group IDs.

RETURN VALUE
       On success, zero is returned.  On error, -1 is returned, and errno is set
       to indicate the error.

ERRORS
       EFAULT One of the arguments specified an address outside the calling
              program's address space.

VERSIONS
       These system calls appeared on Linux starting with kernel 2.1.44.

       The prototypes are given by glibc since version 2.3.2, provided
       _GNU_SOURCE is defined.

CONFORMING TO
       These calls are nonstandard; they also appear on HP-UX and some of the
       BSDs.

NOTES
       The original Linux getresuid() and getresgid() system calls supported
       only 16-bit user and group IDs.  Subsequently, Linux 2.4 added
       getresuid32() and getresgid32(), supporting 32-bit IDs.  The glibc
       getresuid() and getresgid() wrapper functions transparently deal with the
       variations across kernel versions.

SEE ALSO
       getuid(2), setresuid(2), setreuid(2), setuid(2), credentials(7)

COLOPHON
       This page is part of release 5.13 of the Linux man-pages project.  A
       description of the project, information about reporting bugs, and the
       latest version of this page, can be found at
       https://www.kernel.org/doc/man-pages/.



Linux                              2021-03-22                       GETRESUID(2)