diff options
author | Guido van Rossum <guido@python.org> | 1994-09-12 10:36:35 (GMT) |
---|---|---|
committer | Guido van Rossum <guido@python.org> | 1994-09-12 10:36:35 (GMT) |
commit | 23cb2a83a5e709761e8f649371a935f7b676ea10 (patch) | |
tree | b335064154564741754b8cd2ee4aec998b1fcbc8 /Lib/pty.py | |
parent | c0af2aafeb8fbbba05e65b7e833f23b49a7af2a2 (diff) | |
download | cpython-23cb2a83a5e709761e8f649371a935f7b676ea10.zip cpython-23cb2a83a5e709761e8f649371a935f7b676ea10.tar.gz cpython-23cb2a83a5e709761e8f649371a935f7b676ea10.tar.bz2 |
New tty/pty modules by Steen; new urlparser.
Diffstat (limited to 'Lib/pty.py')
-rw-r--r-- | Lib/pty.py | 106 |
1 files changed, 106 insertions, 0 deletions
diff --git a/Lib/pty.py b/Lib/pty.py new file mode 100644 index 0000000..53a4b2d --- /dev/null +++ b/Lib/pty.py @@ -0,0 +1,106 @@ +# pty.py -- Pseudo terminal utilities. + +# Bugs: No signal handling. Doesn't set slave termios and window size. +# Only tested on Linux. +# See: W. Richard Stevens. 1992. Advanced Programming in the +# UNIX Environment. Chapter 19. +# Author: Steen Lumholt -- with additions by Guido. + +from select import select +import os, sys, FCNTL +import tty + +STDIN_FILENO = 0 +STDOUT_FILENO = 1 +STDERR_FILENO = 2 + +CHILD = 0 + +# Open pty master. Returns (master_fd, tty_name). SGI and Linux/BSD version. +def master_open(): + try: + import sgi + except ImportError: + pass + else: + try: + tty_name, master_fd = sgi._getpty(FCNTL.O_RDWR, 0666, 0) + except IOError, msg: + raise os.error, msg + return master_fd, tty_name + for x in 'pqrstuvwxyzPQRST': + for y in '0123456789abcdef': + pty_name = '/dev/pty' + x + y + try: + fd = os.open(pty_name, FCNTL.O_RDWR) + except os.error: + continue + return (fd, '/dev/tty' + x + y) + raise os.error, 'out of pty devices' + +# Open the pty slave. Acquire the controlling terminal. +# Returns file descriptor. Linux version. (Should be universal? --Guido) +def slave_open(tty_name): + return os.open(tty_name, FCNTL.O_RDWR) + +# Fork and make the child a session leader with a controlling terminal. +# Returns (pid, master_fd) +def fork(): + master_fd, tty_name = master_open() + pid = os.fork() + if pid == CHILD: + # Establish a new session. + os.setsid() + + # Acquire controlling terminal. + slave_fd = slave_open(tty_name) + os.close(master_fd) + + # Slave becomes stdin/stdout/stderr of child. + os.dup2(slave_fd, STDIN_FILENO) + os.dup2(slave_fd, STDOUT_FILENO) + os.dup2(slave_fd, STDERR_FILENO) + if (slave_fd > STDERR_FILENO): + os.close (slave_fd) + + # Parent and child process. + return pid, master_fd + +# Write all the data to a descriptor. +def writen(fd, data): + while data != '': + n = os.write(fd, data) + data = data[n:] + +# Default read function. +def read(fd): + return os.read(fd, 1024) + +# Parent copy loop. +# Copies +# pty master -> standard output (master_read) +# standard input -> pty master (stdin_read) +def copy(master_fd, master_read=read, stdin_read=read): + while 1: + rfds, wfds, xfds = select( + [master_fd, STDIN_FILENO], [], []) + if master_fd in rfds: + data = master_read(master_fd) + os.write(STDOUT_FILENO, data) + if STDIN_FILENO in rfds: + data = stdin_read(STDIN_FILENO) + writen(master_fd, data) + +# Create a spawned process. +def spawn(argv, master_read=read, stdin_read=read): + if type(argv) == type(''): + argv = (argv,) + pid, master_fd = fork() + if pid == CHILD: + apply(os.execlp, (argv[0],) + argv) + mode = tty.tcgetattr(STDIN_FILENO) + tty.setraw(STDIN_FILENO) + try: + copy(master_fd, master_read, stdin_read) + except: + tty.tcsetattr(STDIN_FILENO, tty.TCSAFLUSH, mode) |