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.

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 4.04 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
       http://www.kernel.org/doc/man-pages/.

                                                   2015-08-08                                        UNLOCKPT(3)