|GETUID(2)||System Calls Manual||GETUID(2)|
LIBRARY¶Standard C Library (libc, -lc)
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.
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)
getuid() system calls are expected to conform to IEEE Std 1003.1-1990 (“POSIX.1”).
getuid() function appeared in Version 1 AT&T UNIX. The
geteuid() function appeared in Version 4 AT&T UNIX.
|December 1, 2017||Linux 4.19.0-6-amd64|