unlockpt

(3)

unlock a pseudoterminal master/slave pair

#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 glibc 2.23 and earlier: _XOPEN_SOURCE

LIBRARY

Standard C library (libc, -lc)

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 to indicate the error.

ERRORS

EBADF: The fd argument is not a file descriptor open for writing.
EINVAL: The fd argument is not associated with a master pseudoterminal.

ATTRIBUTES

For an explanation of the terms used in this section, see attributes(7).

Interface	Attribute	Value
unlockpt ()	Thread safety	MT-Safe

STANDARDS

POSIX.1-2008.

HISTORY

glibc 2.1. POSIX.1-2001.