unlockpt(3p) — Linux manual page

UNLOCKPT(3P)            POSIX Programmer's Manual            UNLOCKPT(3P)

PROLOG         top

       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.

NAME         top

       unlockpt — unlock a pseudo-terminal master/slave pair

SYNOPSIS         top

       #include <stdlib.h>

       int unlockpt(int fildes);

DESCRIPTION         top

       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         top

       Upon successful completion, unlockpt() shall return 0. Otherwise,
       it shall return -1 and set errno to indicate the error.

ERRORS         top

       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.

EXAMPLES         top

       None.

APPLICATION USAGE         top

       None.

RATIONALE         top

       See the RATIONALE section for posix_openpt(3p).

FUTURE DIRECTIONS         top

       None.

SEE ALSO         top

       grantpt(3p), open(3p), posix_openpt(3p), ptsname(3p)

       The Base Definitions volume of POSIX.1‐2017, stdlib.h(0p)

COPYRIGHT         top

       Portions of this text are reprinted and reproduced in electronic
       form from IEEE Std 1003.1-2017, Standard for Information
       Technology -- Portable Operating System Interface (POSIX), The
       Open Group Base Specifications Issue 7, 2018 Edition, Copyright
       (C) 2018 by the Institute of Electrical and Electronics Engineers,
       Inc and The Open Group.  In the event of any discrepancy between
       this version and the original IEEE and The Open Group Standard,
       the original IEEE and The Open Group Standard is the referee
       document. The original Standard can be obtained online at
       http://www.opengroup.org/unix/online.html .

       Any typographical or formatting errors that appear in this page
       are most likely to have been introduced during the conversion of
       the source files to man page format. To report such errors, see
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .

IEEE/The Open Group                2017                      UNLOCKPT(3P)

Pages that refer to this page: stdlib.h(0p),  grantpt(3p),  open(3p),  posix_openpt(3p),  ptsname(3p)

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