Section: Linux Programmer's Manual (3)
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posix_openpt - open a pseudoterminal device
int posix_openpt(int flags);
Feature Test Macro Requirements for glibc (see
_XOPEN_SOURCE >= 600
function opens an unused pseudoterminal master device, returning a
file descriptor that can be used to refer to that device.
argument is a bit mask that ORs together zero or more of
the following flags:
Open the device for both reading and writing.
It is usual to specify this flag.
Do not make this device the controlling terminal for the process.
returns a nonnegative file descriptor which is the lowest
numbered unused descriptor.
On failure, -1 is returned, and
is set to indicate the error.
Glibc support for
has been provided since version 2.2.1.
Multithreading (see pthreads(7))
function is thread-safe.
is part of the UNIX 98 pseudoterminal support (see
This function is specified in POSIX.1-2001.
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:
return open("/dev/ptmx", flags);
creates a pathname for the corresponding pseudoterminal slave device.
The pathname of the slave device can be obtained using
The slave device pathname exists only as long as the master device is open.
This page is part of release 3.74 of the Linux
A description of the project,
information about reporting bugs,
and the latest version of this page,
can be found at
- RETURN VALUE
- Multithreading (see pthreads(7))
- CONFORMING TO
- SEE ALSO