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listen [2006/08/29 20:18] (current) – created - external edit 127.0.0.1
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 +# $EPIC: listen.txt,v 1.3 2006/08/29 18:22:56 sthalik Exp $
 +======Synopsis:======
 +$__listen__() \\
 +$__listen__(<port> [family])
 +
 +======Technical:======
 +   * The __listen__ function establishes a passive TCP connection (``server'').
 +   * The <port> argument is optional and if provided is taken as a number.
 +   * If the <port> argument is not a number, the empty string is returned.
 +   * If the <port> argument is not zero and less than 1024, the empty string is returned.
 +   * The optional family argument can be 4, 6, v4, or v6, and tells the client whether it should bind to IPv4 or IPv6.
 +   * If the requested port is not available (probably because it is in use by someone else), an error is output and the empty string is returned.
 +   * The return value is the local port number associated with the connection.
 +
 +======Practical:======
 +If you want your script to act as an Internet server, the $listen()
 +function lets you establish a place where others can $[[connect
 +function|connect]]() to you.  Once they $[[connect function|connect]]()
 +to you, you are given a small integer that acts in the same way that
 +$[[connect function|connect]]() return values do.
 +
 +======Returns:======
 +The port number being listened on, or the empty string on error.
 +
 +======Examples:======
 +<file>
 +$listen(1025)             returns 1025
 +$listen(1023)             error, returns nothing
 +$listen(0)                returns a system-allocated port number
 +$listen()                 returns a system-allocated port number
 +</file>
 +
 +======History:======
 +This function first appeared in ircII-2.2pre3
  
listen.txt · Last modified: 2006/08/29 20:18 by 127.0.0.1