NAME
posix_openpt - open a pseudo-terminal device
SYNOPSIS
#define _XOPEN_SOURCE 600
#include <stdlib.h>
#include <fcntl.h>
I int posix_openpt(int flags );
DESCRIPTION
The
R posix_openpt ()
function opens an unused pseudo-terminal 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.
RETURN VALUE
On success,
R posix_openpt ()
returns a non-negative file descriptor which is the lowest
numbered unused descriptor.
On failure, -1 is returned, and
errno
is set to indicate the error.
ERRORS
VERSIONS
Glibc support for
R posix_openpt ()
has been provided since version 2.2.1.
CONFORMING TO
R posix_openpt ()
is part of the Unix98 pseudo-terminal support (see
pts(4)).
This function is specified in POSIX.1-2001.
NOTES
This function is a recent invention in POSIX.
Some Unix implementations that support System V
(aka Unix 98) pseudo-terminals don't have this function, but it
is easy to implement:
int
posix_openpt(int flags)
{
return open("/dev/ptmx", flags);
}
SEE ALSO