plan9 man page for null

Query: null

OS: plan9

Section: 3tcl

Format: Original Unix Latex Style Formatted with HTML and a Horizontal Scroll Bar

null(3tcl)																null(3tcl)

NAME
null - Create and manipulate null channels
SYNOPSIS
package require Tcl package require memchan null
DESCRIPTION
The command described here is only available in a not-yet released version of the package. Use the CVS to get the sources. null 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). Transfer- ring the generated channel between interpreters is possible but does not make much sense.
OPTIONS
Memory channels created by null provide one additional option to set or query. -delay ?milliseconds? 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.
SEE ALSO
fifo, fifo2, memchan, random, zero
KEYWORDS
channel, i/o, in-memory channel, null
COPYRIGHT
Copyright (c) 1996-2003 Andreas Kupries <andreas_kupries@users.sourceforge.net> Memory channels 2.2 null(3tcl)
Related Man Pages
null(0x9da423) - mojave
null(0x9da426) - mojave
null(3tcl) - minix
null(3tcl) - xfree86
null(3tcl) - posix
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