xref: /illumos-gate/usr/src/man/man3c/grantpt.3c (revision bbf215553c7233fbab8a0afdf1fac74c44781867)

.\"
.\" Sun Microsystems, Inc. gratefully acknowledges The Open Group for
.\" permission to reproduce portions of its copyrighted documentation.
.\" Original documentation from The Open Group can be obtained online at
.\" http://www.opengroup.org/bookstore/.
.\"
.\" The Institute of Electrical and Electronics Engineers and The Open
.\" Group, have given us permission to reprint portions of their
.\" documentation.
.\"
.\" In the following statement, the phrase ``this text'' refers to portions
.\" of the system documentation.
.\"
.\" Portions of this text are reprinted and reproduced in electronic form
.\" in the SunOS Reference Manual, from IEEE Std 1003.1, 2004 Edition,
.\" Standard for Information Technology -- Portable Operating System
.\" Interface (POSIX), The Open Group Base Specifications Issue 6,
.\" Copyright (C) 2001-2004 by the Institute of Electrical and Electronics
.\" Engineers, Inc and The Open Group.  In the event of any discrepancy
.\" between these versions 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.
.\"
.\" This notice shall appear on any product containing this material.
.\"
.\" The contents of this file are subject to the terms of the
.\" Common Development and Distribution License (the "License").
.\" You may not use this file except in compliance with the License.
.\"
.\" You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
.\" or http://www.opensolaris.org/os/licensing.
.\" See the License for the specific language governing permissions
.\" and limitations under the License.
.\"
.\" When distributing Covered Code, include this CDDL HEADER in each
.\" file and include the License file at usr/src/OPENSOLARIS.LICENSE.
.\" If applicable, add the following below this CDDL HEADER, with the
.\" fields enclosed by brackets "[]" replaced with your own identifying
.\" information: Portions Copyright [yyyy] [name of copyright owner]
.\"
.\"
.\" Copyright 1989 AT&T
.\" Portions Copyright (c) 1994, X/Open Company Limited.  All Rights Reserved.
.\" Copyright (c) 2006, Sun Microsystems, Inc.  All Rights Reserved.
.\" Copyright 2022 Oxide Computer Company
.\"
.Dd February 5, 2022
.Dt GRANTPT 3C
.Os
.Sh NAME
.Nm grantpt
.Nd grant access to the subsidiary device of a pseudo-terminal
.Sh SYNOPSIS
.In stdlib.h
.Ft int
.Fo grantpt
.Fa "int fildes"
.Fc
.Sh DESCRIPTION
The
.Fn grantpt
function changes the mode and ownership of the pseudo-terminal subsidiary
device associated with its pseudo-terminal manager counterpart.
.Pp
The
.Fa fildes
argument is the file descriptor returned from a successful
.Xr open 2
of the pseudo-terminal manager device; e.g., by calling
.Xr posix_openpt 3C
or by performing an
.Xr open 2
of the
.Xr ptm 4D
device.
.Pp
The user ID owner of the subsidiary device is set to the real user ID of the
calling process.
The group ID owner is set to a reserved group.
.Pp
The permission mode of the subsidiary device is set to be readable and writable
by the owner, and writable by the group.
.Sh RETURN VALUES
.Rv -std grantpt
.Sh EXAMPLES
See
.Xr posix_openpt 3C
for an example that includes a call to
.Fn grantpt .
.Sh ERRORS
The
.Fn grantpt
function may fail if:
.Bl -tag -width Er
.It Er EBADF
The
.Fa fildes
argument is not a valid open file descriptor.
.It Er EINVAL
The
.Fa fildes
argument is not associated with a pseudo-terminal manager device.
.It Er EACCES
The corresponding pseudo-terminal subsidiary device could not be accessed.
.El
.Sh INTERFACE STABILITY
.Sy Committed
.Sh MT LEVEL
.Sy Safe
.Sh SEE ALSO
.Xr open 2 ,
.Xr posix_openpt 3C ,
.Xr ptsname 3C ,
.Xr unlockpt 3C ,
.Xr ptm 4D ,
.Xr attributes 7 ,
.Xr standards 7