UNLOCKPT

Section: Linux Programmer's Manual (3)
Updated: 2017-07-13
Index Return to Main Contents

---

 

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 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

This page is part of release 4.13 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/.

---

 

Index

NAME

SYNOPSIS

DESCRIPTION

RETURN VALUE

ERRORS

VERSIONS

ATTRIBUTES

CONFORMING TO

SEE ALSO

COLOPHON