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SOCKET(1)		    General Commands Manual		     SOCKET(1)

       socket -	create tcp socket and connect to stdin/out

       socket [	-bcfqrvw ] [ -p	command	] host port
       socket [	-bcfqrvw ] [ -p	command	] -s [ -l ] port

       Socket  creates	an Internet domain TCP socket and connects it to stdin
       and stdout.  The	host argument can be an	Internet number	 in  dot-nota-
       tion (like ``'') or	a domain name. In this case it must be
       possible	to resolve the name to a valid Internet	address	with  gethost-
       byname(3).   The	 port  argument	can be a port number or	a service name
       which can be mapped to a	port number by getservbyname(3).

       -b (background)
	      The program forks	itself into the	background, detaches from  its
	      controlling tty, closes the file descriptors associated with the
	      tty, and changes its current directory to	the root directory.

       -c (crlf)
	      Linefeed characters (LF) are  converted  to  a  Carriage	Return
	      Linefeed	sequence  (CRLF) when written to the socket.  CRLF se-
	      quences read from	the socket are converted to a single LF.

       -f (fork)
	      When a server connection has been	accepted, a  separate  process
	      is forked	to handle the connection in background.

       -l (loop)
	      (only valid with -s) After a connection has been closed, another
	      connection is accepted.

       -p (program)
	      The specified command is executed	for each connection. Its stan-
	      dard  input,  standard  output,  and standard error channels are
	      connected	to the socket.	Command	can be any shell command since
	      it is passed to /bin/sh.

       -q (quit)
	      The connection is	closed when an end-of-file condition occurs on
	      standard input.

       -r (read	only)
	      No data is read from standard input and written to the socket.

       -s (server)
	      A	server socket is created.  A  hostname	argument  is  not  re-

       -v (verbose)
	      Messages about connections etc. are issued to stderr.

       -w (write only)
	      No data is read from the socket and written to the standard out-

	      Socket prints its	version	ID and terminates.  This must  be  the
	      first argument to	have an	effect.

       The command

	      socket -v nntp

       connects	  to   the   nntp  port	 (port	119)  of
       The command

	      socket -sl 3425

       creates a server	socket on port 3425 on the local host and waits	for  a
       connection.   After  a  connection has been closed, a new connection is
       The command

	      socket -wslqvp "echo Socket! " 1938

       creates a server	socket on port 1938 on the local host and waits	for  a
       connection.   When  a  connection  is accepted, the string "Socket!" is
       written to the socket.  No data is read from the	socket and written  to
       the  finger program.  The connection is closed when an end-of-file con-
       dition at the standard output of	the program  occurs.  Then a new  con-
       nection is accepted.

       Lots of diagnostics for failed system calls.

       unknown host host
	      host's address could not be resolved.

       Signal signal caught, exiting
	      Socket  exits on any signal other	than SIGTSTP, SIGCONT, SIGCLD,

       A non-zero exit code is returned	if socket terminates due to  an	 error
       condition or a signal.

       accept(2), bind(2), connect(2), socket(2), gethostbyname(3), getservby-

       socket -p terminates due	to a SIGPIPE signal when there	is  more  data
       from the	socket available than the executed program wants to read.

       Please report any other bugs to the author.

       This manual page	describes Socket-1.1.

       Juergen Nickelsen <>

				 Aug  6, 1992			     SOCKET(1)


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