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POSIX_OPENPT(2)		      System Calls Manual	       POSIX_OPENPT(2)

NAME
       posix_openpt -- open a pseudo-terminal device

LIBRARY
       Standard	C Library (libc, -lc)

SYNOPSIS
       #include	<fcntl.h>
       #include	<stdlib.h>

       int
       posix_openpt(int	oflag);

DESCRIPTION
       The  posix_openpt() function allocates a	new pseudo-terminal and	estab-
       lishes a	connection with	its master device.  A slave  device  shall  be
       created in /dev/pts.  After the pseudo-terminal has been	allocated, the
       slave  device  should have the proper permissions before	it can be used
       (see grantpt(3)).  The name of the slave	device can  be	determined  by
       calling ptsname(3).

       The  file  status flags and file	access modes of	the open file descrip-
       tion shall be set according to the value	of oflag.   Values  for	 oflag
       are  constructed	 by a bitwise-inclusive	OR of flags from the following
       list, defined in	<fcntl.h>:

       O_RDWR	  Open for reading and writing.

       O_NOCTTY	  If set posix_openpt()	shall not cause	the terminal device to
		  become the controlling terminal for the process.

       O_CLOEXEC  Set the close-on-exec	flag for the new file descriptor.

       The posix_openpt() function shall fail when oflag contains  other  val-
       ues.

RETURN VALUES
       Upon  successful	completion, the	posix_openpt() function	shall allocate
       a new pseudo-terminal device and	return a non-negative  integer	repre-
       senting	a  file	 descriptor,  which is connected to its	master device.
       Otherwise, -1 shall be returned and errno set to	indicate the error.

ERRORS
       The posix_openpt() function shall fail if:

       [ENFILE]		  The system file table	is full.

       [EINVAL]		  The value of oflag is	not valid.

       [EAGAIN]		  Out of pseudo-terminal resources.

SEE ALSO
       ptsname(3), pts(4), tty(4)

STANDARDS
       The  posix_openpt()  function  conforms	 to   IEEE   Std   1003.1-2001
       ("POSIX.1").  The ability to use	O_CLOEXEC is an	extension to the stan-
       dard.

HISTORY
       The  posix_openpt()  function appeared in FreeBSD 5.0.  In FreeBSD 8.0,
       this function was changed to a system call.

NOTES
       The flag	O_NOCTTY is included for compatibility;	in FreeBSD, opening  a
       terminal	does not cause it to become a process's	controlling terminal.

AUTHORS
       Ed Schouten <ed@FreeBSD.org>

FreeBSD	13.2		      September	21, 2016	       POSIX_OPENPT(2)
NAME | LIBRARY | SYNOPSIS | DESCRIPTION | RETURN VALUES | ERRORS | SEE ALSO | STANDARDS | HISTORY | NOTES | AUTHORS

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