NAME
getuid, geteuid
— get user
identification
LIBRARY
library “libc”
SYNOPSIS
#include
<unistd.h>
uid_t
getuid(void);
uid_t
geteuid(void);
DESCRIPTION
Thegetuid()
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
STANDARDS
The geteuid() and
getuid() system calls are expected to conform to
IEEE Std 1003.1-1990 (“POSIX.1”).
HISTORY
The getuid() function appeared in
Version 1 AT&T UNIX. The
geteuid() function appeared in
Version 4 AT&T UNIX.