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null(7) [osf1 man page]

null(7) 						 Miscellaneous Information Manual						   null(7)

NAME
null - Data sink DESCRIPTION
Data written on a null special file are discarded. Reads from a null special file always return 0 (zero) bytes. EXAMPLES
To read a floppy disk and display the total number of records read in and output to /dev/null using the dd command: dd if=/dev/disk/floppy0 of=/dev/null To create a zero length file using the cat command: cat > foo < /dev/null FILES
/dev/null delim off null(7)

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null(n) 																   null(n)

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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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