sock(1) sock-1.1 sock(1)
UCW Utilities UCW Utilities
12 June 2001
NAME
sock - simple socket interface for shell scripts
SYNOPSIS
sock [-dentuvx] ([-b <local>] <remote> | -l <local>) [<command>]
DESCRIPTION
sock is a simple program serving as an interface between its standard
input/output streams and sockets, primarily intended to be used in
shell scripts, but often useful interactively from the command line as
well.
sock supports two modes: listening mode and originating mode. In the
listening mode (requested by the -l option), sock acts as an server
and accepts incoming connections for the network address specified as
<local> (see below for how to write addresses). In the originating
mode, you specify an address (<remote>) to connect to and maybe also
the local address (-b <local>) to bind the local end to.
By default, sock just copies its standard input to the socket and all
data received from the socket to its standard output. If you want, you
can specify a <command> to be spawned and the socket redirected to its
standard input/output instead (in the listening mode, you can use -d
to wait for multiple connections and spawn the command for each of
them instead of exiting after serving a single incoming connection).
ADDRESSES
sock currently supports two address families: IP and UNIX.
For UNIX domain sockets, just use a socket file name as an address.
For IP (TCP/UDP) sockets, addresses look like [<host>][:<port>], where
<host> is a host name and <port> is a port number or a service name.
In case you don't specify whether you want to use TCP or UDP, sock
uses the protocol associated with the specified service or falls back
to TCP if both are possible. If the host name is omitted, "any" (for
binding or listening) or "localhost" (for connecting) is assumed.
OPTIONS
-d Run as a daemon and run the <command> for each incoming
connection instead of exiting after having served a single
connection.
-e Terminate after receiving first EOF in any direction. Default
behaviour is to wait for EOF in both directions. Please note that
this has changed since version 1.0.
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sock(1) sock-1.1 sock(1)
UCW Utilities UCW Utilities
12 June 2001
-n Avoid reverse DNS lookups in verbose mode.
-t Open a TCP socket.
-u Open a UDP socket.
-v Be verbose. The more -v's you give, the more verbose sock is.
-x Open a UNIX socket.
EXAMPLES
Use `sock :smtp' to talk with local mailer.
Use `echo -e "HELO `hostname -f`\nETRN `hostname -f`" | sock
mail.server.name:smtp' to tell your mail-exchanger it should start
sending all messages queued for you.
Use `sock -dl :7777 fortune' to establish a simple fortune cookie
server.
Use `sock -e :7777' as a client for the above server.
AUTHOR
sock has been written and is (at least sometimes) maintained by Martin
Mares <mj@ucw.cz>.
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