geteuid(2)

NAME

   getuid, geteuid - get user identity

SYNOPSIS

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

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

DESCRIPTION

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

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

ERRORS

   These functions are always successful.

CONFORMING TO

   POSIX.1-2001, POSIX.1-2008, 4.3BSD.

NOTES

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

   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

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

COLOPHON

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