unlockpt(3) unlock a pseudoterminal master/slave pair

SYNOPSIS

#define _XOPEN_SOURCE /* See feature_test_macros(7) */
#include <stdlib.h>


int unlockpt(int fd);

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).
InterfaceAttributeValue
unlockpt() Thread safetyMT-Safe

CONFORMING TO

POSIX.1-2001, POSIX.1-2008.

COLOPHON

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