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POSIX_OPENPT(2)		    BSD	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 cre-
     ated 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 description
     shall be set according to the value of oflag.  Values for oflag are con-
     structed by a bitwise-inclusive OR	of flags from the following list, de-
     fined 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 values.

RETURN VALUES
     Upon successful completion, the posix_openpt() function shall allocate a
     new pseudo-terminal device	and return a non-negative integer representing
     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 standard.

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>

BSD			      September	21, 2016			   BSD
NAME | LIBRARY | SYNOPSIS | DESCRIPTION | RETURN VALUES | ERRORS | SEE ALSO | STANDARDS | HISTORY | NOTES | AUTHORS

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