POSIX_OPENPT(3) manual page
Table of Contents
posix_openpt - open a pseudoterminal device
#include <stdlib.h>#include <fcntl.h>
int posix_openpt(int flags);
Feature Test Macro Requirements for glibc
(see feature_test_macros(7)
):
posix_openpt(): _XOPEN_SOURCE >= 600
The
posix_openpt() function opens an unused pseudoterminal master device, returning
a file descriptor that can be used to refer to that device.
The flags argument
is a bit mask that ORs together zero or more of the following flags:
- O_RDWR
- Open the device for both reading and writing. It is usual to specify this
flag.
- O_NOCTTY
- Do not make this device the controlling terminal for the
process.
On success, posix_openpt() returns a nonnegative file
descriptor which is the lowest numbered unused descriptor. On failure, -1
is returned, and errno is set to indicate the error.
See open(2)
.
Glibc
support for posix_openpt() has been provided since version 2.2.1.
The posix_openpt() function is thread-safe.
posix_openpt()
is part of the UNIX 98 pseudoterminal support (see pts(4)
). This function
is specified in POSIX.1-2001.
The posix_openpt() function is a recent
invention in POSIX. Some UNIX implementations that support System V (aka
UNIX 98) pseudoterminals don’t have this function, but it is easy to implement:
int
posix_openpt(int flags)
{
return open("/dev/ptmx", flags);
}
Calling posix_openpt() creates a pathname for the corresponding pseudoterminal
slave device. The pathname of the slave device can be obtained using ptsname(3)
.
The slave device pathname exists only as long as the master device is open.
open(2)
, getpt(3)
, grantpt(3)
, ptsname(3)
, unlockpt(3)
, pts(4)
,
pty(7)
This page is part of release 3.78 of the Linux man-pages project.
A description of the project, information about reporting bugs, and the
latest version of this page, can be found at http://www.kernel.org/doc/man-pages/.
Table of Contents
![[Go to CFHT Home Page]](/images/cfht-icon.gif){kind=icon}
Man Pages 
Back to Software Index 
Manpage Top Level