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Shell Programming and Scripting

replace first instance(not first instance in line)

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# 1  
Old 02-07-2008
replace first instance(not first instance in line)
Alright, I think I know what I am doing with sed(which probably means I don't). But I cant figure out how to replace just the first occurance of a string. I have tried sed, ed, and grep but can't seem to figure it out. If you have any suggestions I am open to anything!
# 2  
Old 02-07-2008
By "first occurance" do you mean first occurance in a line or first occurance in a file?
# 3  
Old 02-07-2008
Assuming it is the first occurance in a file, the following example should show you how to
do what you want to do using awk.

Code:
$ cat file
true line1
true line2
$ awk '/true/ && n == 0 { sub(/true/,"false"); ++n } { print }' file
false line1
true line2
$

# 4  
Old 02-07-2008
Thank you
You are awsome, THANKS!
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