UNLOCKPT(3) Linux Programmer's Manual UNLOCKPT(3)
NAME
unlockpt - unlock a pseudoterminal master/slave pair
SYNOPSIS
#define _XOPEN_SOURCE
#include <stdlib.h>
int unlockpt(int fd);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
unlockpt():
Since glibc 2.24:
_XOPEN_SOURCE >= 500 ||
(_XOPEN_SOURCE && _XOPEN_SOURCE_EXTENDED)
Glibc 2.23 and earlier:
_XOPEN_SOURCE
DESCRIPTION
The unlockpt() function unlocks the slave pseudoterminal device corre-
sponding to the master pseudoterminal referred to by fd.
unlockpt() should be called before opening the slave side of a pseu-
doterminal.
RETURN VALUE
When successful, unlockpt() returns 0. Otherwise, it returns -1 and
sets errno appropriately.
ERRORS
EBADF The fd argument is not a file descriptor open for writing.
EINVAL The fd argument is not associated with a master pseudoterminal.
VERSIONS
unlockpt() is provided in glibc since version 2.1.
ATTRIBUTES
For an explanation of the terms used in this section, see at-
tributes(7).
+-----------+---------------+---------+
|Interface | Attribute | Value |
+-----------+---------------+---------+
|unlockpt() | Thread safety | MT-Safe |
+-----------+---------------+---------+
CONFORMING TO
POSIX.1-2001, POSIX.1-2008.
SEE ALSO
grantpt(3), posix_openpt(3), ptsname(3), pts(4), pty(7)
COLOPHON
This page is part of release 5.07 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
https://www.kernel.org/doc/man-pages/.
2017-07-13 UNLOCKPT(3)