posix_openpt - open a pseudoterminal device
int posix_openpt(int flags);
Feature Test Macro Requirements for glibc (see feature_test_macros
(): _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
- Open the device for both reading and writing. It is usual to specify this
- 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 file descriptor. On failure, -1 is returned, and
is set to indicate the error.
Glibc support for posix_openpt
() has been provided since version 2.2.1.
For an explanation of the terms used in this section, see attributes
() is part of the UNIX 98 pseudoterminal support (see
Some older 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
(3). The slave device pathname exists only as long as the
master device is open.