Initializing files to empty in korn shell


 
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# 1  
Old 08-11-2008
Initializing files to empty in korn shell

hello,

i want to know how to initialize a file to an empty one in korn shell scripting? i'm using a file name and building it during a while loop using >>. The problem occurs when the file is not empty before reaching the while loop. therefore, i want to initialize it before the loop to get rid of any prior data.. how can i do that with korn shell scripting?

thanks
# 2  
Old 08-11-2008
This will overwrite OR create the file

Code:
echo "" > /path/to/filename

# 3  
Old 08-11-2008
thanks Ikon, but this creates an empty line at the beginning of the file. how can i achieve the same result withouth the beginning empty line?
# 4  
Old 08-11-2008
Code:
cat /dev/null > /path/to/filename

# 5  
Old 08-11-2008
thank you soooo much!
# 6  
Old 08-12-2008
or a more "elegant" way

if [ -e /path/to/file ]
rm /path/to/file
fi

altho that is an uncesesary if, you can simple try to rm it and disble output

rm /path/to/file > /dev/null 2>&1
# 7  
Old 08-12-2008
Adding more shell commands matters while running shell script as it invoke subshell.
IMO echoing is good option. as echo is a builtin command. Smilie

- nilesh
 
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