NAME | SYNOPSIS | DESCRIPTION | ERRORS | CONFORMING TO | NOTES | NOTES | SEE ALSO | COLOPHON

The Linux Programming Interface

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

NAME         top

       getuid, geteuid - get user identity

SYNOPSIS         top

       #include <unistd.h>
       #include <sys/types.h>

       uid_t getuid(void);
       uid_t geteuid(void);

DESCRIPTION         top

       getuid() returns the real user ID of the calling process.

       geteuid() returns the effective user ID of the calling process.

ERRORS         top

       These functions are always successful.

CONFORMING TO         top

       POSIX.1-2001, 4.3BSD.

NOTES         top

History

       In UNIX V6 the getuid() call returned (euid << 8) + uid.  UNIX V7 introduced
       separate calls getuid() and geteuid().

NOTES         top

       The original Linux getuid() and geteuid() system calls supported only 16-bit
       user IDs.  Subsequently, Linux 2.4 added getuid32() and geteuid32(),
       supporting 32-bit IDs.  The glibc getuid() and geteuid() wrapper functions
       transparently deal with the variations across kernel versions.

SEE ALSO         top

       getresuid(2), setreuid(2), setuid(2), credentials(7)

COLOPHON         top

       This page is part of release 3.32 of the Linux man-pages project.  A
       description of the project, and information about reporting bugs, can be found
       at http://www.kernel.org/doc/man-pages/.

Linux                                 2010-11-22                            GETUID(2)

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