NAME
posix_openpt —
open a pseudo-terminal
device
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <stdlib.h>
#include <fcntl.h>
int
posix_openpt(
int
oflag);
DESCRIPTION
The
posix_openpt() function searches for an unused master
pseudo-terminal device, opens it, and returns a file descriptor associated
with the now used pseudo-terminal device. The
oflag
argument has the same meaning as in the
open(2) call.
RETURN VALUES
If successful,
posix_openpt() returns a non-negative integer,
which corresponds to a file descriptor pointing to the master pseudo-terminal
device. Otherwise, a value of -1 is returned and
errno
is set to indicate the error.
SEE ALSO
ioctl(2),
open(2),
grantpt(3),
ptsname(3),
unlockpt(3)
RATIONALE
The standards committee did not want to directly expose the cloning device, thus
decided to wrap the functionality in this function. The equivalent code would
be:
int
posix_openpt(int oflag) {
return open("/dev/ptmx", oflag);
}
STANDARDS
The
posix_openpt() function conforms to
IEEE
Std 1003.1-2001 (“POSIX.1”).