NAME¶
tcl::chan::halfpipe - In-memory channel, half of a fifo2
SYNOPSIS¶
package require
Tcl 8.5
package require
TclOO
package require
tcl::chan::events ?1?
package require
tcl::chan::halfpipe ?1?
package require
tcl::chan::halfpipe ?1?
::tcl::chan::halfpipe ?
-option value...?
objectCmd put bytes
DESCRIPTION¶
The
tcl::chan::halfpipe package provides a command creating one half of a
tcl::chan::fifo2 pair. Writing into such a channel invokes a set of
callbacks which then handle the data. This is similar to a channel handler,
except having a much simpler API.
The internal
TclOO class implementing the channel handler is a sub-class
of the
tcl::chan::events framework.
API¶
- ::tcl::chan::halfpipe ?-option value...?
- This command creates a halfpipe channel and configures it with the
callbacks to run when the channel is closed, data was written to it, or
ran empty. See the section Options for the list of options and
associated semantics. The result of the command is a list containing two
elements, the handle of the new channel, and the object command of the
channel handler, in this order. The latter is supplied to the caller to
provide her with access to the put method for adding data to the
channel.
Two halfpipes with a bit of glue logic in the callbacks make for one
tcl::chan::fifo2.
- objectCmd put bytes
- This method of the channel handler object puts the data bytes into
the channel so that it can be read from it.
OPTIONS¶
- -close-command cmdprefix
- This callback is invoked when the channel is closed. A single argument is
supplied, the handle of the channel being closed. The result of the
callback is ignored.
- -write-command cmdprefix
- This callback is invoked when data is written to the channel. Two
arguments are supplied, the handle of the channel written to, and the data
written. The result of the callback is ignored.
- -empty-command cmdprefix
- This callback is invoked when the channel has run out of data to read. A
single argument is supplied, the handle of the channel.
BUGS, IDEAS, FEEDBACK¶
This document, and the package it describes, will undoubtedly contain bugs and
other problems. Please report such in the category
virtchannel of the
Tcllib Trackers [
http://core.tcl.tk/tcllib/reportlist]. Please also
report any ideas for enhancements you may have for either package and/or
documentation.
KEYWORDS¶
callbacks, fifo, in-memory channel, reflected channel, tip 219, virtual channel
CATEGORY¶
Channels
COPYRIGHT¶
Copyright (c) 2009 Andreas Kupries <andreas_kupries@users.sourceforge.net>