unix-sockets

  1. unix-sockets
    1. Description
    2. Author
    3. Requirements
    4. Documentation
    5. Gotchas
    6. Changelog
    7. License

Description

Simple access to UNIX domain sockets.

Author

felix winkelmann

Requirements

easyffi

Documentation

The interface is similar to the builtin TCP socket functionality in CHICKEN.

[procedure] (unix-listen PATHNAME [BACKLOG])

Creates a socket listener object. PATHNAME gives the name of the file that represents the connection. BACKLOG specifies how many pending connections are allowed and defaults to 10.

[procedure] (unix-listener? X)

Returns #t if X is a unix socket listener object, or #f otherwise.

[procedure] (unix-close LISTENER)

Closes the socket associated with the listener object.

[procedure] (unix-accept LISTENER)

Waits for a connection from a client and returns two values: an input- and output-port which can be used to communicate with the connecting process. Calling unix-accept does not block other threads from running.

[procedure] (unix-accept-ready? LISTENER)

Returns #t if a unix-accept for this listener would not block the current thread, or #f otherwise.

[procedure] (unix-connect PATHNAME)

Connects to the socket given in PATHNAME and returns two values: an input- and output-port which allow communication with the server.

[procedure] (unix-listener-fileno LISTENER)

Returns the file-descriptor of the socket associated with the given listener object.

[procedure] (unix-listener-path LISTENER)

Returns the pathname of the socket associated with the given listener object.

[procedure] (unix-pair)

Create a pair of connected sockets and returns four values: an input- and output-port for the first socket, and the same for the second socket. These ports can be used for bidirectional communication between a parent and child process, for example.

Gotchas

If you try to write to the socket's output port when the other side has shut down the socket, a SIGPIPE will be generated. The application must handle or ignore the signal (see posix); once the signal is dealt with, the write attempt will raise an exception of its own using signal from Exceptions.

Changelog

License

 Copyright (c) 2005, Felix L. Winkelmann
 All rights reserved.
 
 Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following
 conditions are met:
 
   Redistributions of source code must retain the above copyright notice, this list of conditions and the following
     disclaimer. 
   Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following
     disclaimer in the documentation and/or other materials provided with the distribution. 
   Neither the name of the author nor the names of its contributors may be used to endorse or promote
     products derived from this software without specific prior written permission. 
 
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