UNLOCKPT
Section: POSIX Programmer's Manual (3P)
Updated: 2017
Page Index
PROLOG
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.
NAME
unlockpt
--- unlock a pseudo-terminal master/slave pair
SYNOPSIS
#include <stdlib.h>
int unlockpt(int fildes);
DESCRIPTION
The
unlockpt()
function shall unlock the slave pseudo-terminal device associated with
the master to which
fildes
refers.
Conforming applications shall ensure that they call
unlockpt()
before opening the slave side of a pseudo-terminal device.
RETURN VALUE
Upon successful completion,
unlockpt()
shall return 0. Otherwise, it shall return -1 and set
errno
to indicate the error.
ERRORS
The
unlockpt()
function may fail if:
- EBADF
-
The
fildes
argument is not a file descriptor open for writing.
- EINVAL
-
The
fildes
argument is not associated with a master pseudo-terminal device.
The following sections are informative.
EXAMPLES
None.
APPLICATION USAGE
None.
RATIONALE
See the RATIONALE section for
posix_openpt().
FUTURE DIRECTIONS
None.
SEE ALSO
grantpt(),
open(),
posix_openpt(),
ptsname()
The Base Definitions volume of POSIX.1-2017,
<stdlib.h>
COPYRIGHT
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 .
Any typographical or formatting errors that appear
in this page are most likely
to have been introduced during the conversion of the source files to
man page format. To report such errors, see
https://www.kernel.org/doc/man-pages/reporting_bugs.html .