grantpt(3)
NAME
grantpt - grant access to the slave pseudo-terminal
SYNOPSIS
#define _XOPEN_SOURCE #include <stdlib.h> int grantpt(int fd);
DESCRIPTION
The grantpt() function changes the mode and owner of the slave pseudoterminal device (pty) corresponding to the master pty referred to by
fd. The user ID of the slave is set to the real UID of the calling
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 pty 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 pty.
VERSIONS
grantpt() is provided in glibc since version 2.1.
CONFORMING TO
POSIX.1-2001.
NOTES
This is part of the Unix98 pty 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), feature_test_macros(7), pty(7)
COLOPHON
- This page is part of release 3.25 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/.