| OPENPTY(3) | Library Functions Manual | OPENPTY(3) |
openpty,
login_tty, forkpty —
tty utility functions
#include
<util.h>
int
openpty(int
*aprimary, int
*areplica, char
*name, struct termios
*termp, struct winsize
*winp);
int
login_tty(int
fd);
pid_t
forkpty(int
*aprimary, char
*name, struct termios
*termp, struct winsize
*winp);
The
openpty(),
login_tty(), and forkpty()
functions perform manipulations on ttys and pseudo-ttys.
The
openpty()
function allocates a pseudo-tty and returns file descriptors for the primary
and replica in aprimary and
areplica. If name is non-null,
the filename of the replica is returned in name. If
termp is non-null, the terminal parameters of the
replica will be set to the values in termp. If
winp is non-null, the window size of the replica will
be set to the values in winp.
The
login_tty()
function prepares for a login on the tty fd (which may
be a real tty device, or the replica of a pseudo-tty as returned by
openpty()) by creating a new session, making
fd the controlling terminal for the current process,
setting fd to be the standard input, output, and error
streams of the current process, and closing fd.
The
forkpty()
function combines openpty(),
fork(),
and login_tty() to creates a new process operating
in a pseudo-tty. The file descriptor of the primary side of the pseudo-tty
is returned in aprimary, and the filename of the
replica in name if it is non-null. The
termp and winp parameters, if
non-null, will determine the terminal attributes and window size of the
replica side of the pseudo-tty.
If a call to openpty(),
login_tty(), or forkpty() is
not successful, -1 is returned and errno is set to
indicate the error. Otherwise, openpty(),
login_tty(), and the child process of
forkpty() return 0, and the parent process of
forkpty() returns the process ID of the child
process.
openpty() will fail if:
EAGAIN]login_tty() will fail if
ioctl() fails to set fd to the
controlling terminal of the current process.
forkpty() will fail if either
openpty() or fork()
fails.
| April 5, 2008 | Mac OS X 12 |