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null(7d) [opensolaris man page]

null(7D)							      Devices								  null(7D)

NAME
null - the null file, also called the null device SYNOPSIS
/dev/null DESCRIPTION
Data written on the null special file, /dev/null, is discarded. Reads from a null special file always return 0 bytes. Mapping a null special file creates an address reservation of a length equal to the length of the mapping, and rounded up to the nearest page size as returned by sysconf(3C). No resources are consumed by the reservation. Mappings can be placed in the resulting address range via subsequent calls to mmap with the -MAP_FIXED option set. FILES
/dev/null SEE ALSO
mmap(2), sysconf(3C) SunOS 5.11 4 April 2001 null(7D)

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null(n) 																   null(n)

__________________________________________________________________________________________________________________________________________________

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- ing 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(n)
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