SYNOPSIS

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

DESCRIPTION

       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 ``130.149.28.10'') 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).

OPTIONS

       -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
              sequences 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
              required.

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

       -w (write only)
       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
       accepted.
       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.

DIAGNOSTICS

       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,
              SIGQUIT.

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

SEE ALSO

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

BUGS

       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.

VERSION

       This manual page describes Socket-1.1.

AUTHOR

       Juergen Nickelsen <jn@berlin.snafu.de>



                                 Aug  6, 1992                        SOCKET(1)