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Emptying a file (bring the size of the file down to 0 , or close to 0)

 
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# 1  
Old 07-13-2010
Emptying a file (bring the size of the file down to 0 , or close to 0)
Hi

I tried to empty an existing file (bring the size of the file down to 0). When I used “> myFile” or “cat </dev/null >myFile”, when I do a “ls –la”, the file size shows as 0.

I then wrote 540 lines to the file, and then opened it using vi, I see something like this:
"myFile" 540 lines, 6533391 characters (6490635 null)

Seems like the commands above did not realease the disk space. They simply converted all characters to null characters (which are still taking up space). Does anyone know how to empty a file and make the file size go to zero (or close to zero)?

Thanks a lot Smilie

Tom
# 2  
Old 07-13-2010
what happens if you: # touch <filename>?

edit: just took a look at the man page - there doesn't seem to be a flag to recreate the file only creates if it's not there in the first place.
Last edited by Celtic_Monkey; 07-13-2010 at 11:46 AM..
# 3  
Old 07-13-2010
Quote:
Originally Posted by Celtic_Monkey
what happens if you: # touch <filename>?
Unfortunately it's the same result.
# 4  
Old 07-13-2010
Perhaps the file is open by a program which needs to be stopped before nulling the file?

Code:
fuser -f filename

 
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