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how to save changes to a file

 
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# 1  
Old 08-10-2010
how to save changes to a file
is i want to sort or delete lines etc etc to a file, how do i save the changes.

example i do sort file > file
when i do cat file, all data is erased.
thanks.
# 2  
Old 08-10-2010
Output to a temporary file, and then move it over top of the original file. The trick is to not overlay the original file if the command fails.

Code:
#!/usr/bin/env ksh

# straight forward:
if sort file >file.tmp
then
    mv file.tmp file
fi


# less than straight forward, but same effect
sort file >file.tmp && mv file.tmp file

This User Gave Thanks to agama For This Post:
hobiwhenuknowme
# 3  
Old 08-11-2010
thank you.
 
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