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tcl::chan::fifo - Reflected/virtual channel support
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tcl::chan::fifo(n) 1 tcllib "Reflected/virtual channel support"


tcl::chan::fifo - In-memory fifo channel


  • package require Tcl 8.5
  • package require TclOO
  • package require tcl::chan::events ?1?
  • package require tcl::chan::fifo ?1?


The tcl::chan::fifo package provides a command creating channels which live purely in memory. Access is fifo-like, i.e. things are read out of the channel in the order they were written to it. This is equivalent to the fifo channels provided by the package Mmechan, except that this is written in pure Tcl, not C. On the other hand, Memchan is usable with Tcl 8.4 and before, whereas this package requires Tcl 8.5 or higher, and TclOO.

The internal TclOO class implementing the channel handler is a sub-class of the tcl::chan::events framework.



This command creates a new fifo channel and returns its handle.

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. Please also report any ideas for enhancements you may have for either package and/or documentation.