I have a file that has the word "snake" in it
There is a snake in the first line. No such word in the second line. Another snake in the 3rd line. There is a blue snake and a red snake here.
This one-liner that you can run on the command line will replace the word "snake" by the word "camel" in the file:
$ perl -i -p -e 's/snake/camel/g' snakes_or_camels.txt
This one-liner will create a backup of the original file before making the changes.
$ perl -i.bak -p -e 's/snake/camel/g' snakes_or_camels.txt
-imeans "inplace editing"
-i.bakmeans "copy to .bak then inplace editing"
-pmeans (in rough terms) "What ever you do, do it on every line of data."
-emeans "execute the following code".
s/snake/camel/gis a substitution. The
gat the end means globally. Without that only the first snake would be replaced.
The result is
There is a camel in the first line. No such word in the second line. Another camel in the 3rd line. There is a blue camel and a red camel here.
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