$listen()
Synopsis
$listen()
$listen(<port> [<family>])
Technical
Retained as a compatibility placeholder. The current built-in always returns the empty string. It does not parse or validate arguments, bind a port, create a listening socket, accept connections, or produce connection diagnostics.
The historical port and family arguments, including 4, 6, v4, and v6, have no effect. Omitting the port or supplying zero does not request a system-allocated port in the current implementation. There are no active port-range checks or address-family options.
Practical
Existing scripts can still call the function, but cannot use it to act as a TCP server or obtain a listening port. The related connect function is also a compatibility placeholder.
Returns
Always the empty string, regardless of arguments.
Examples
| Expression | Result |
|---|---|
$listen(1025) |
Empty string |
$listen(1023) |
Empty string |
$listen(0) |
Empty string |
$listen() |
Empty string |
None of these opens a socket or reserves a port.
History
This function first appeared in ircII-2.2pre3. Its former passive TCP listener implementation is disabled in the current source.
Source
Registered and implemented as function_listen in source/functions.c. The former implementation is inside #if 0; the active branch returns the empty string unconditionally.