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)
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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)
Hi,
I would like to know which files contain a certain string. If I use 'grep "string" *' only the working directory is being searched. I also want to search the subdirectories. When I use 'find . -type f -print |xargs grep "string" > dev/null' I get the message 'xargs: missing quote?'. What's... (11 Replies)
im having trouble with moving files in a directory into /dev/null
for file in $HOME/.trashcan/
do
mv $file /dev/null
done
the error msg i get is:
mv: /dev/null: not a directory.
does anyone know how to fix this?
thanks
primal (16 Replies)
Hi, Anyone can help
My solaris 8 system has the following
/dev/null , /dev/tty and /dev/console
All permission are lrwxrwxrwx
Can this be change to a non-world write ??
any impact ?? (12 Replies)
hi all,
iam new to this forum.i have to submit the script EOD.so please help me.
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We have a code to find the DNS entry of a host that has a trailing '-' in its url (format example: mysite-.watch.com):
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{
//failed
}
But when remove the '-' from the host name the code does not return... (12 Replies)
Hi All,
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hi,
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Hi,
after a server (solaris 10) got rebooted, Im faced with the problem that in one of my zones (whole zone) /dev/null is only writeable for root
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Unfortunatly chmod didnt help at this point and since its a productive system I dont... (11 Replies)
Hi all,
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1.3 1.1 NaN 1.3 NaN
2.4 1.3 1.5 NaN 1.5
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Hi,
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Hi,
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20130516|00000061|02210|111554|03710|2|205069|SM APPL $80-100 RTL|S
20130516|00000061|02210|111554|03710|2|205069|SM APPL $80-100 RTL|S... (12 Replies)
I am working on a file with several columns as below
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RXOCF-101,BTS INTERNAL,FAULT CODES CLASS 2A,53,58
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Hi All
My requirement is to find the null values in particular column of a file and reject it in case if it contains null values. But the challenge is that I want a common command which can be used across different file, as the position of the column we need to check for different file may get... (14 Replies)