1zero(n) zero(n)
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8 zero - Create and manipulate zero channels
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11 package require Tcl
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13 package require memchan
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15 zero
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20 The command described here is only available in a not-yet released ver‐
21 sion of the package. Use the CVS to get the sources.
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23 zero creates a zero channel which absorbs everything written into it.
24 Reading from a zero channel will return the requested number of
25 null bytes. These channels are essentially Tcl-specific variants
26 of the zero device for unixoid operating systems (/dev/zero).
27 Transferring the generated channel between interpreters is pos‐
28 sible but does not make much sense.
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31 Memory channels created by zero provide one additional option to set or
32 query.
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34 -delay ?milliseconds?
35 A zero channel is always writable and readable. This means that
36 all fileevent-handlers will fire continuously. To avoid starva‐
37 tion of other event sources the events raised by this channel
38 type have a configurable delay. This option is set in millisec‐
39 onds and defaults to 5.
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42 fifo, fifo2, memchan, null, random
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45 channel, i/o, in-memory channel, null, zero
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48 Copyright (c) 2004 Pat Thoyts <patthoyts@users.sourceforge.net>
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53Memory channels 2.2 zero(n)