The
openpty(),
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 (to the parent process only) in
amaster. The filename of the slave is returned (to both the parent and child processes) in
name if
name 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.