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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.

       When  a  normal  program is executed, the effective and real user ID of
       the process are set to the ID of the user executing the file.   When  a
       set  ID program is executed the real user ID is set to the calling user
       and the effective user ID corresponds to the set ID  bit  on  the  file
       being executed.

ERRORS

       These functions are always successful.

CONFORMING TO

       POSIX.1-2001, 4.3BSD.

NOTES

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

SEE ALSO

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

COLOPHON

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