unlockpt(3) - Linux man page

Name

unlockpt - 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.

Conforming to

POSIX.1-2001.

See Also

grantpt(3), posix_openpt(3), ptsname(3), pts(4), pty(7)

Referenced By

getpt(3)