GRANTPT(3) Linux Programmer's Manual GRANTPT(3)
NAME
grantpt - grant access to the slave pseudoterminal
SYNOPSIS
#define _XOPEN_SOURCE /* See feature_test_macros(7) */
#include <stdlib.h>
int grantpt(int fd);
DESCRIPTION
The grantpt() function changes the mode and owner of the slave pseu-
doterminal device corresponding to the master pseudoterminal referred
to by fd. The user ID of the slave is set to the real UID of the call-
ing process. The group ID is set to an unspecified value (e.g., tty).
The mode of the slave is set to 0620 (crw--w----).
The behavior of grantpt() is unspecified if a signal handler is
installed to catch SIGCHLD signals.
RETURN VALUE
When successful, grantpt() returns 0. Otherwise, it returns -1 and
sets errno appropriately.
ERRORS
EACCES The corresponding slave pseudoterminal could not be accessed.
EBADF The fd argument is not a valid open file descriptor.
EINVAL The fd argument is valid but not associated with a master pseu-
doterminal.
VERSIONS
grantpt() is provided in glibc since version 2.1.
CONFORMING TO
POSIX.1-2001.
NOTES
This is part of the UNIX 98 pseudoterminal support, see pts(4). Many
systems implement this function via a set-user-ID helper binary called
"pt_chown". With Linux devpts no such helper binary is required.
SEE ALSO
open(2), posix_openpt(3), ptsname(3), unlockpt(3), pts(4), pty(7)
COLOPHON
This page is part of release 3.53 of the Linux man-pages project. A
description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/man-pages/.
GNU 2008-06-14 GRANTPT(3)