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.
setegid — set the effective group ID
int setegid(gid_t gid);
If gid is equal to the real group ID or the saved set-group-ID, or if the
process has appropriate privileges, setegid() shall set the effective
group ID of the calling process to gid; the real group ID, saved
set-group-ID, and any supplementary group IDs shall remain unchanged.
The setegid() 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 setegid() function shall fail if:
- The value of the gid argument is invalid and is not supported by
- The process does not have appropriate privileges and gid 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(), seteuid(),
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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