Initial revision
diff --git a/Demo/sockets/README b/Demo/sockets/README
new file mode 100644
index 0000000..463ab1c
--- /dev/null
+++ b/Demo/sockets/README
@@ -0,0 +1,7 @@
+Contents of this directory:
+
+echosvr.py About the simplest TCP server possible.
+finger.py Client for the 'finger' protocol.
+telnet.py Client for the 'telnet' protocol.
+throughput.py Client and server to measure TCP throughput.
+udpecho.py Client and server for the UDP echo protocol.
diff --git a/Demo/sockets/echosvr.py b/Demo/sockets/echosvr.py
new file mode 100755
index 0000000..f245583
--- /dev/null
+++ b/Demo/sockets/echosvr.py
@@ -0,0 +1,31 @@
+#! /usr/local/python
+
+# Python implementation of an 'echo' tcp server: echo all data it receives.
+#
+# This is the simplest possible server, sevicing a single request only.
+
+import sys
+from socket import *
+
+# The standard echo port isn't very useful, it requires root permissions!
+# ECHO_PORT = 7
+ECHO_PORT = 50000 + 7
+BUFSIZE = 1024
+
+def main():
+ if len(sys.argv) > 1:
+ port = int(eval(sys.argv[1]))
+ else:
+ port = ECHO_PORT
+ s = socket(AF_INET, SOCK_STREAM)
+ s.bind('', port)
+ s.listen(0)
+ conn, (host, remoteport) = s.accept()
+ print 'connected by', host, remoteport
+ while 1:
+ data = conn.recv(BUFSIZE)
+ if not data:
+ break
+ conn.send(data)
+
+main()
diff --git a/Demo/sockets/finger.py b/Demo/sockets/finger.py
new file mode 100755
index 0000000..8aa0535
--- /dev/null
+++ b/Demo/sockets/finger.py
@@ -0,0 +1,58 @@
+#! /usr/local/python
+
+# Python interface to the Internet finger daemon.
+#
+# Usage: finger [options] [user][@host] ...
+#
+# If no host is given, the finger daemon on the local host is contacted.
+# Options are passed uninterpreted to the finger daemon!
+
+
+import sys, string
+from socket import *
+
+
+# Hardcode the number of the finger port here.
+# It's not likely to change soon...
+#
+FINGER_PORT = 79
+
+
+# Function to do one remote finger invocation.
+# Output goes directly to stdout (although this can be changed).
+#
+def finger(host, args):
+ s = socket(AF_INET, SOCK_STREAM)
+ s.connect(host, FINGER_PORT)
+ s.send(args + '\n')
+ while 1:
+ buf = s.recv(1024)
+ if not buf: break
+ sys.stdout.write(buf)
+ sys.stdout.flush()
+
+
+# Main function: argument parsing.
+#
+def main():
+ options = ''
+ i = 1
+ while i < len(sys.argv) and sys.argv[i][:1] = '-':
+ options = options + sys.argv[i] + ' '
+ i = i+1
+ args = sys.argv[i:]
+ if not args:
+ args = ['']
+ for arg in args:
+ if '@' in arg:
+ at = string.index(arg, '@')
+ host = arg[at+1:]
+ arg = arg[:at]
+ else:
+ host = ''
+ finger(host, options + arg)
+
+
+# Call the main function.
+#
+main()
diff --git a/Demo/sockets/telnet.py b/Demo/sockets/telnet.py
new file mode 100755
index 0000000..60f832a
--- /dev/null
+++ b/Demo/sockets/telnet.py
@@ -0,0 +1,109 @@
+#! /usr/local/python
+
+# Minimal interface to the Internet telnet protocol.
+#
+# It refuses all telnet options and does not recognize any of the other
+# telnet commands, but can still be used to connect in line-by-line mode.
+# It's also useful to play with a number of other services,
+# like time, finger, smtp and even ftp.
+#
+# Usage: telnet host [port]
+#
+# The port may be a service name or a decimal port number;
+# it defaults to 'telnet'.
+
+
+import sys, posix, time
+from socket import *
+
+BUFSIZE = 1024
+
+# Telnet protocol characters
+
+IAC = chr(255) # Interpret as command
+DONT = chr(254)
+DO = chr(253)
+WONT = chr(252)
+WILL = chr(251)
+
+def main():
+ host = sys.argv[1]
+ try:
+ hostaddr = gethostbyname(host)
+ except error:
+ sys.stderr.write(sys.argv[1] + ': bad host name\n')
+ sys.exit(2)
+ #
+ if len(sys.argv) > 2:
+ servname = sys.argv[2]
+ else:
+ servname = 'telnet'
+ #
+ if '0' <= servname[:1] <= '9':
+ port = eval(servname)
+ else:
+ try:
+ port = getservbyname(servname, 'tcp')
+ except error:
+ sys.stderr.write(servname + ': bad tcp service name\n')
+ sys.exit(2)
+ #
+ s = socket(AF_INET, SOCK_STREAM)
+ #
+ try:
+ s.connect(host, port)
+ except error, msg:
+ sys.stderr.write('connect failed: ' + `msg` + '\n')
+ sys.exit(1)
+ #
+ pid = posix.fork()
+ #
+ if pid = 0:
+ # child -- read stdin, write socket
+ while 1:
+ line = sys.stdin.readline()
+ s.send(line)
+ else:
+ # parent -- read socket, write stdout
+ iac = 0 # Interpret next char as command
+ opt = '' # Interpret next char as option
+ while 1:
+ data = s.recv(BUFSIZE)
+ if not data:
+ # EOF; kill child and exit
+ sys.stderr.write( '(Closed by remote host)\n')
+ posix.kill(pid, 9)
+ sys.exit(1)
+ cleandata = ''
+ for c in data:
+ if opt:
+ print ord(c)
+ s.send(opt + c)
+ opt = ''
+ elif iac:
+ iac = 0
+ if c = IAC:
+ cleandata = cleandata + c
+ elif c in (DO, DONT):
+ if c = DO: print '(DO)',
+ else: print '(DONT)',
+ opt = IAC + WONT
+ elif c in (WILL, WONT):
+ if c = WILL: print '(WILL)',
+ else: print '(WONT)',
+ opt = IAC + DONT
+ else:
+ print '(command)', ord(c)
+ elif c = IAC:
+ iac = 1
+ print '(IAC)',
+ else:
+ cleandata = cleandata + c
+ sys.stdout.write(cleandata)
+ sys.stdout.flush()
+
+
+try:
+ main()
+except KeyboardInterrupt:
+ pass
diff --git a/Demo/sockets/throughput.py b/Demo/sockets/throughput.py
new file mode 100755
index 0000000..411af9f
--- /dev/null
+++ b/Demo/sockets/throughput.py
@@ -0,0 +1,93 @@
+#! /usr/local/python
+
+# Test network throughput.
+#
+# Usage:
+# 1) on host_A: throughput -s [port] # start a server
+# 2) on host_B: throughput -c count host_A [port] # start a client
+#
+# The server will service multiple clients until it is killed.
+#
+# The client performs one transfer of count*BUFSIZE bytes and
+# measures the time it takes (roundtrip!).
+
+
+import sys, time
+from socket import *
+
+MY_PORT = 50000 + 42
+
+BUFSIZE = 1024
+
+
+def main():
+ if len(sys.argv) < 2:
+ usage()
+ if sys.argv[1] = '-s':
+ server()
+ elif sys.argv[1] = '-c':
+ client()
+ else:
+ usage()
+
+
+def usage():
+ sys.stdout = sys.stderr
+ print 'Usage: (on host_A) throughput -s [port]'
+ print 'and then: (on host_B) throughput -c count host_A [port]'
+ sys.exit(2)
+
+
+def server():
+ if len(sys.argv) > 2:
+ port = eval(sys.argv[2])
+ else:
+ port = MY_PORT
+ s = socket(AF_INET, SOCK_STREAM)
+ s.bind('', port)
+ s.listen(0)
+ print 'Server ready...'
+ while 1:
+ conn, (host, remoteport) = s.accept()
+ while 1:
+ data = conn.recv(BUFSIZE)
+ if not data:
+ break
+ del data
+ conn.send('OK\n')
+ conn.close()
+ print 'Done with', host, 'port', remoteport
+
+
+def client():
+ if len(sys.argv) < 4:
+ usage()
+ count = int(eval(sys.argv[2]))
+ host = sys.argv[3]
+ if len(sys.argv) > 4:
+ port = eval(sys.argv[4])
+ else:
+ port = MY_PORT
+ testdata = 'x' * (BUFSIZE-1) + '\n'
+ t1 = time.millitimer()
+ s = socket(AF_INET, SOCK_STREAM)
+ t2 = time.millitimer()
+ s.connect(host, port)
+ t3 = time.millitimer()
+ i = 0
+ while i < count:
+ i = i+1
+ s.send(testdata)
+ s.shutdown(1) # Send EOF
+ t4 = time.millitimer()
+ data = s.recv(BUFSIZE)
+ t5 = time.millitimer()
+ print data
+ print 'Raw timers:', t1, t2, t3, t4, t5
+ print 'Intervals:', t2-t1, t3-t2, t4-t3, t5-t4
+ print 'Total:', t5-t1
+ print 'Throughput:', int(float(BUFSIZE*count) / float(t5-t1)),
+ print 'K/sec.'
+
+
+main()
diff --git a/Demo/sockets/udpecho.py b/Demo/sockets/udpecho.py
new file mode 100755
index 0000000..53dff64
--- /dev/null
+++ b/Demo/sockets/udpecho.py
@@ -0,0 +1,63 @@
+#! /usr/local/python
+
+# Client and server for udp (datagram) echo.
+#
+# Usage: udpecho -s [port] (to start a server)
+# or: udpecho -c host [port] <file (client)
+
+import sys
+from socket import *
+
+ECHO_PORT = 50000 + 7
+BUFSIZE = 1024
+
+def main():
+ if len(sys.argv) < 2:
+ usage()
+ if sys.argv[1] = '-s':
+ server()
+ elif sys.argv[1] = '-c':
+ client()
+ else:
+ usage()
+
+def usage():
+ sys.stdout = sys.stderr
+ print 'Usage: udpecho -s [port] (server)'
+ print 'or: udpecho -c host [port] <file (client)'
+ sys.exit(2)
+
+def server():
+ if len(sys.argv) > 2:
+ port = eval(sys.argv[2])
+ else:
+ port = ECHO_PORT
+ s = socket(AF_INET, SOCK_DGRAM)
+ s.bind('', port)
+ print 'udp echo server ready'
+ while 1:
+ data, addr = s.recvfrom(BUFSIZE)
+ print 'server received', `data`, 'from', `addr`
+ s.sendto(data, addr)
+
+def client():
+ if len(sys.argv) < 3:
+ usage()
+ host = sys.argv[2]
+ if len(sys.argv) > 3:
+ port = eval(sys.argv[3])
+ else:
+ port = ECHO_PORT
+ addr = host, port
+ s = socket(AF_INET, SOCK_DGRAM)
+ s.bind('', 0)
+ print 'udp echo client ready, reading stdin'
+ while 1:
+ line = sys.stdin.readline()
+ if not line:
+ break
+ s.sendto(line, addr)
+ data, fromaddr = s.recvfrom(BUFSIZE)
+ print 'client received', `data`, 'from', `fromaddr`
+
+main()