POSIX_OPENPT

Section: Linux Programmer's Manual (3)
Updated: 2004-12-17
Index Return to Main Contents
 

NAME

posix_openpt - open a pseudo-terminal device  

SYNOPSIS

#define _XOPEN_SOURCE

#include <stdlib.h> #include <fcntl.h> char *posix_openpt(int flags);
 

DESCRIPTION

The posix_openpt() function opens an unused pseudo-terminal 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.
 

RETURN VALUE

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

ERRORS

See open(2).  

CONFORMING TO

posix_openpt() is part of the Unix98 pseudo-terminal support (see pts(4)). This function is specified in POSIX.1-2001.  

NOTES

This function is a recent invention in POSIX. Some Unix implementations that support System V (aka Unix 98) pseudo-terminals don't have this function, but it is easy to implement:

int
posix_openpt(int flags)
{
    return open("/dev/ptmx", flags);
}
 

SEE ALSO

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


 

Index

NAME
SYNOPSIS
DESCRIPTION
RETURN VALUE
ERRORS
CONFORMING TO
NOTES
SEE ALSO

linux.jgfs.net manual pages