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Old 01-09-2008, 10:23 AM   #1
shtek
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Registered: Jan 2008
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piping and redirecting files


I want to trim some of the log files and hence i want to do something like

ls -la | grep log

this will give me a list of log files

for each log file I want to do
echo ""> filename

but i need to do it for each file so if i could combine these two command together thats great, bt dont know how..
 
Old 01-09-2008, 10:42 AM   #2
dive
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something like:

Code:
for log in `ls -la | grep log`
do
echo "" > $log
done
(untested)
 
Old 01-09-2008, 10:53 AM   #3
ghostdog74
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use shell expansion
Code:
for log in *log*
do
echo "" > $log
done
 
Old 01-09-2008, 11:28 AM   #4
colucix
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Just a side note: if the intent of the command
Code:
echo "" > logfile
is to clear the content of the file, you would use one of the following instead
Code:
: > logfile

echo -n > logfile
The former is the "null command", the latter is to avoid the trailing "newline" character. Indeed, if you simply overwrite the file with a zero-length string, the result will be a 1-byte file (and subsequent writes will leave a blank line at the beginning of the file).
 
Old 01-15-2008, 09:39 AM   #5
shtek
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thanks

That worked >!!!!!!
 
  


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