UNLOCKPT
Section: Linux Programmer's Manual (3)
Updated: 2017-07-13
Page Index
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
corresponding to the master pseudoterminal referred to by the file descriptor
fd.
unlockpt()
should be called before opening the slave side of a pseudoterminal.
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
attributes(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
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man-pages
project.
A description of the project,
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and the latest version of this page,
can be found at
https://www.kernel.org/doc/man-pages/.