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

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.

NAME
       grantpt -- grant access to the slave pseudo-terminal device

SYNOPSIS
       #include <stdlib.h>

       int grantpt(int fildes);

DESCRIPTION
       The grantpt() function shall change the mode and ownership of the slave
       pseudo-terminal device associated with its master pseudo-terminal
       counterpart. The fildes argument is a file descriptor that refers to a
       master pseudo-terminal device. The user ID of the slave shall be set to
       the real UID of the calling process and the group ID shall be set to an
       unspecified group ID. The permission mode of the slave pseudo-terminal
       shall be set to readable and writable by the owner, and writable by the
       group.

       The behavior of the grantpt() function is unspecified if the
       application has installed a signal handler to catch SIGCHLD signals.

RETURN VALUE
       Upon successful completion, grantpt() shall return 0; otherwise, it
       shall return -1 and set errno to indicate the error.

ERRORS
       The grantpt() function may fail if:

       EACCES The corresponding slave pseudo-terminal device could not be
              accessed.

       EBADF  The fildes argument is not a valid open file descriptor.

       EINVAL The fildes argument is not associated with a master pseudo-
              terminal device.

       The following sections are informative.

EXAMPLES
       None.

APPLICATION USAGE
       None.

RATIONALE
       See the RATIONALE section for posix_openpt().

FUTURE DIRECTIONS
       None.

SEE ALSO
       open(), posix_openpt(), ptsname(), unlockpt()

       The Base Definitions volume of POSIX.1-2017, <stdlib.h>

COPYRIGHT
       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                          GRANTPT(3P)