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Shell Programming and Scripting

writing in a file's particular column number of every line during runtime

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# 8  
Old 09-03-2011
is there any way to reflect this change in the original file?
# 9  
Old 09-03-2011
Look at the post #2 in this thread.
# 10  
Old 09-03-2011
Quote:
Originally Posted by arindamlive
i have this following file named test.txt whose content is

Hello
World

Whats Up?


and i execute the following command
x="Hey"
awk -v LINE=3 -v COL=1 -v VAL="x" '{ if(NR == LINE) $COL=VAL } 1' test.txt /tmp/$$
That's not precisely what I suggested. You left out some characters as well as leaving out two important steps.

You never said x was a variable, either. I'll have to change it for that.

Code:
awk -v LINE=3 -v COL=1 -v VAL="$x" '{ if(NR == LINE) $COL=VAL } 1' test.txt > /tmp/$$
cat /tmp/$$ > test.txt
rm test.txt

Really though -- is editing-in-place such a good idea? At least test your data somehow before overwriting it.
This User Gave Thanks to Corona688 For This Post:
arindamlive
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