int
openpty(int *amaster, int *aslave, char *name, struct termios *termp, struct winsize *winp)
int
login_tty(int fd)
pid_t
forkpty(int *amaster, char *name, struct termios *termp, struct winsize *winp)
),
login_tty(),
and
forkpty()
functions perform manipulations on ttys and pseudo-ttys.
The
openpty()
function finds an available pseudo-tty and returns file descriptors
for the master and slave in
amaster
and
aslave.
If
name
is non-null, the filename of the slave is returned in
name.
If
termp
is non-null, the terminal parameters of the slave will be set to the
values in
termp.
If
winp
is non-null, the window size of the slave 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 slave 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 create a new process operating in a pseudo-tty.
The file descriptor of the master side of the pseudo-tty is returned in
amaster,
and the filename of the slave 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 slave side of the pseudo-tty.
),
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.
/dev/[pt]ty[p-zP-T][0-9a-zA-Z])
will fail if:
ENOENT]EPERM]
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.