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Top Forums Shell Programming and Scripting Null values after emptying a log file Post 56612 by kasie4life on Wednesday 6th of October 2004 11:22:50 AM
Old 10-06-2004
Null values after emptying a log file

Hi,

I have a log file which is constantly being written to by some process. I need to clear that log file on a daily basis.

The problem is that when I issue this command:

echo "" > logfile.log

the file gets filled with nulls thus increasing the size of the file.

Is there a way to pause/stop the process, then copy the logfile to some name and then clearing the original logfile, then restarting the paused/stopped process?

I am doing all this in a shell script.

Thanx

Regards
2me
 

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LOGSAVE(8)						      System Manager's Manual							LOGSAVE(8)

NAME
logsave - save the output of a command in a logfile SYNOPSIS
logsave [ -asv ] logfile cmd_prog [ ... ] DESCRIPTION
The logsave program will execute cmd_prog with the specified argument(s), and save a copy of its output to logfile. If the containing directory for logfile does not exist, logsave will accumulate the output in memory until it can be written out. A copy of the output will also be written to standard output. If cmd_prog is a single hyphen ('-'), then instead of executing a program, logsave will take its input from standard input and save it in logfile logsave is useful for saving the output of initial boot scripts until the /var partition is mounted, so the output can be written to /var/log. OPTIONS
-a This option will cause the output to be appended to logfile, instead of replacing its current contents. -s This option will cause logsave to skip writing to the log file text which is bracketed with a control-A (ASCII 001 or Start of Header) and control-B (ASCII 002 or Start of Text). This allows progress bar information to be visible to the user on the console, while not being written to the log file. -v This option will make logsave to be more verbose in its output to the user. AUTHOR
Theodore Ts'o (tytso@mit.edu) SEE ALSO
fsck(8) E2fsprogs version 1.44.1 March 2018 LOGSAVE(8)
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