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.
ERRORS¶
These functions are always successful.
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().
 
The original Linux 
getuid() and 
geteuid() system calls supported
  only 16-bit user IDs. Subsequently, Linux 2.4 added 
getuid32() and
  
geteuid32(), supporting 32-bit IDs. The glibc 
getuid() and
  
geteuid() wrapper functions transparently deal with the variations
  across kernel versions.
SEE ALSO¶
getresuid(2), 
setreuid(2), 
setuid(2), 
credentials(7)
COLOPHON¶
This page is part of release 3.74 of the Linux 
man-pages project. A
  description of the project, information about reporting bugs, and the latest
  version of this page, can be found at
  
http://www.kernel.org/doc/man-pages/.