This manual page is part of the POSIX Programmer's Manual. The Linux
implementation of this interface may differ (consult the corresponding Linux
manual page for details of Linux behavior), or the interface may not be
implemented on Linux.
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 appropriate 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:
- The value of the uid argument is invalid and is not supported by
- The process does not have appropriate privileges and uid does not
match the real user ID or the saved set-user-ID.
The following sections are informative.
Refer to the RATIONALE section in setuid().
exec, getegid(), geteuid(),
getgid(), getuid(), setegid(),
setgid(), setregid(), setreuid(),
The Base Definitions volume of POSIX.1‐2017,
Portions of this text are reprinted and reproduced in electronic form from IEEE
Std 1003.1-2017, Standard for Information Technology -- Portable Operating
System Interface (POSIX), The Open Group Base Specifications Issue 7, 2018
Edition, Copyright (C) 2018 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 original
Standard can be obtained online at http://www.opengroup.org/unix/online.html .
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