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.
