posix_openpt - open a pseudoterminal device

       For an explanation of the terms used in this section, see attributes(7).
       ┌─────────────────────────────────────────────────────────────────────────────┬───────────────┬─────────┐
       │ Interface                                                                   │ Attribute     │ Value   │
       ├─────────────────────────────────────────────────────────────────────────────┼───────────────┼─────────┤
       │ posix_openpt()                                                              │ Thread safety │ MT-Safe │
       └─────────────────────────────────────────────────────────────────────────────┴───────────────┴─────────┘

       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.

       See open(2).

       glibc 2.2.1.  POSIX.1-2001.

       It is part of the UNIX 98 pseudoterminal support (see pts(4)).

       Standard C library (libc, -lc)

       posix_openpt - open a pseudoterminal device

       Some older UNIX implementations that support System V (aka  UNIX  98)  pseudoterminals  don't  have  this
       function, but it can be easily implemented by opening the pseudoterminal multiplexor device:

           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.

       On success, posix_openpt() returns a file descriptor (a nonnegative integer) which is the lowest numbered
       unused file descriptor.  On failure, -1 is returned, and errno is set to indicate the error.

open(2), getpt(3), grantpt(3), ptsname(3), unlockpt(3), pts(4), pty(7)

Linux man-pages 6.9.1                              2024-05-02                                    posix_openpt(3)

       POSIX.1-2008.

#include<stdlib.h>#include<fcntl.h>intposix_openpt(intflags);

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

       posix_openpt():
           _XOPEN_SOURCE >= 600