SETEUID(P) POSIX Programmer's Manual SETEUID(P)
seteuid - set effective user ID
int seteuid(uid_t uid);
If uid is equal to the real user ID or the saved set-user-ID, or if the process has appro-
priate privileges, seteuid() shall set the effective user ID of the calling process to
uid; the real user ID and saved set-user-ID shall remain unchanged.
The seteuid() function shall not affect the supplementary group list in any way.
Upon successful completion, 0 shall be returned; otherwise, -1 shall be returned and errno
set to indicate the error.
The seteuid() function shall fail if:
EINVAL The value of the uid argument is invalid and is not supported by the implementa-
EPERM The process does not have appropriate privileges and uid does not match the real
group ID or the saved set-group-ID.
The following sections are informative.
Refer to the RATIONALE section in setuid() .
exec() , getegid() , geteuid() , getgid() , getuid() , setegid() , setgid() , setregid() ,
setreuid() , setuid() , the Base Definitions volume of IEEE Std 1003.1-2001,
Portions of this text are reprinted and reproduced in electronic form from IEEE Std
1003.1, 2003 Edition, Standard for Information Technology -- Portable Operating System
Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2003 by
the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the
event of any discrepancy between this version and the original IEEE and The Open Group
Standard, the original IEEE and The Open Group Standard is the referee document. The orig-
inal Standard can be obtained online at http://www.opengroup.org/unix/online.html .
IEEE/The Open Group 2003 SETEUID(P)