unlockpt man page

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.

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.

Rationale

See the Rationale section for posix_openpt().

See Also

grantpt(), open(), posix_openpt(), ptsname()

The Base Definitions volume of POSIX.1‐2008, <stdlib.h>

Info

2013 IEEE/The Open Group POSIX Programmer's Manual