Tutorials Point


  Unix for Beginners
  Unix Shell Programming
  Advanced Unix
  Unix Useful References
  Unix Useful Resources
  Selected Reading

Copyright © 2014 by tutorialspoint



  Home     References     Discussion Forums     About TP  

seteuid() - Unix, Linux System Call


previous next AddThis Social Bookmark Button


Advertisements

NAME

seteuid, setegid - set effective user or group ID

SYNOPSIS

#include <sys/types.h> 
#include <unistd.h> 

int seteuid(uid_t euid);
int setegid(gid_t egid);

DESCRIPTION

seteuid() sets the effective user ID of the current process. Unprivileged user processes may only set the effective user ID to the real user ID, the effective user ID or the saved set-user-ID.

Precisely the same holds for setegid() with "group" instead of "user".

RETURN VALUE

On success, zero is returned. On error, -1 is returned, and errno is set appropriately.

ERRORS

TagDescription
EPERM The current process is not privileged (Linux: does not have the CAP_SETUID capability in the case of seteuid(), or the CAP_SETGID capability in the case of setegid()) and euid (resp. egid) is not the real user (group) ID, the effective user (group) ID, or the saved set-user-ID (saved set-group-ID).

NOTES

Setting the effective user (group) ID to the saved set-user-ID (saved set-group-ID) is possible since Linux 1.1.37 (1.1.38). On an arbitrary system one should check _POSIX_SAVED_IDS.

Under libc4, libc5 and glibc2.0 seteuid(euid) is equivalent to setreuid(-1, euid) and hence may change the saved set-user-ID. Under glibc2.1 it is equivalent to setresuid(-1, euid,-1) and hence does not change the saved set-user-ID. Similar remarks hold for setegid().

CONFORMING TO

4.3BSD, POSIX.1-2001.

SEE ALSO



previous next Printer Friendly

Advertisements


  

Advertisements