NAME

       getuid, geteuid — get user identification

LIBRARY

       Standard C Library (libc, -lc)

SYNOPSIS

       #include <unistd.h>

       uid_t
       getuid(void);

       uid_t
       geteuid(void);

DESCRIPTION

       The  getuid()  system  call  returns  the real user ID of the calling process.  The geteuid() system call
       returns the effective user ID of the calling process.

       The real user ID is that of the user who has invoked the program.  As the effective  user  ID  gives  the
       process  additional  permissions  during  execution  of “set-user-ID” mode processes, getuid() is used to
       determine the real-user-id of the calling process.

ERRORS

       The getuid() and geteuid() system calls are always  successful,  and  no  return  value  is  reserved  to
       indicate an error.

SEE ALSO

       getgid(2), issetugid(2), setgid(2), setreuid(2), setuid(2)

STANDARDS

       The geteuid() and getuid() system calls are expected to conform to ISO/IEC 9945-1:1990 (“POSIX.1”).

HISTORY

       The getuid() function appeared in Version 1 AT&T UNIX.  The geteuid() function appeared in Version 4 AT&T
       UNIX.

Debian                                          December 1, 2017                                       GETUID(2)