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Full Discussion: Null values after emptying a log file
Top Forums Shell Programming and Scripting Null values after emptying a log file Post 56624 by RTM on Wednesday 6th of October 2004 12:26:05 PM
Old 10-06-2004
See this post .

Quote:
echo "" > logfile.log

the file gets filled with nulls thus increasing the size of the file.
I tried this and it worked the way expected - removed the contents of the file and left one blank line.

> should cause the file to be truncated to zero length if it exist - and the noclobber option is off.
 

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LEARN ABOUT DEBIAN

httppower

httppower(8)							     powerman							      httppower(8)

NAME

       httppower - communicate with HTTP based power distribution units

SYNOPSIS

       httppower [--url URL]

DESCRIPTION

       httppower  is  a  helper program for powerman which enables it to communicate with HTTP based power distribution units.	It is run interac-
       tively by the powerman daemon.

OPTIONS

       -u, --url URL
	      Set the base URL.

INTERACTIVE COMMANDS

       The following commands are accepted at the httppower> prompt:

       auth user:pass
	      Authenticate to the base URL with specified user and password, using ``basic'' HTTP authentication which sends the user and password
	      over the network in plain text.

       seturl URL
	      Set the base URL.  Overrides the command line option.

       get [URL-suffix]
	      Send an HTTP GET to the base URL with the optional URL-suffix appended.

       post [URL-suffix] key=val[&key=val]...
	      Send an HTTP POST to the base URL with the optional URL-suffix appended, and key-value pairs as argument.

FILES

       /usr/sbin/httppower
       /etc/powerman/powerman.conf

ORIGIN

       PowerMan was originally developed by Andrew Uselton on LLNL's Linux clusters.  This software is open source and distributed under the terms
       of the GNU GPL.

SEE ALSO

       powerman(1), powermand(8), httppower(8), plmpower(8), vpcd(8), powerman.conf(5), powerman.dev(5), powerman-devices(7).

       http://sourceforge.net/projects/powerman

powerman-2.3.5							    2009-02-09							      httppower(8)
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