Manual Reference Pages - NULL (n)
null - Create and manipulate null channels
package require Tcl
package require memchan
The command described here is only available in a not-yet released
version of the package. Use the CVS to get the sources.
creates a null channel which absorbs everything written into
it. Reading from it is not possible, or rather will always return zero
bytes. These channels are essentially Tcl-specific variants of the
null device for unixoid operating systems (/dev/null). Transferring the
generated channel between interpreters is possible but does not make
Memory channels created by null provide one additional option to
set or query.
A null channel is always writable and readable. This means
that all fileevent-handlers will fire continuously. To
avoid starvation of other event sources the events raised by this
channel type have a configurable delay. This option is set in
milliseconds and defaults to 5.
A null channel is always writable and never readable. This means that a
writable fileevent-handler will fire continuously and a readable
fileevent-handler never at all. The exception to the latter is
only the destruction of the channel which will cause the delivery of
an eof event to a readable handler.
fifo, fifo2, memchan, random, zero
channel, i/o, in-memory channel, null
Copyright (c) 1996-2003 Andreas Kupries <email@example.com>
|Memory channels ||NULL (n) ||2&.2 |
Visit the GSP FreeBSD Man Page Interface.
Output converted with manServer 1.07.