Question

For example:
I have a txt file like :

text(“hello”)
text(“world”)
text(“once”)
text(“again”)

Aim to replace 
hello  with string_1,
world with string_2,
once with string_3,
again  with string_4,

How to write the script?

Answer 1

perl -pi -e 's/hello/string_1/g;s/world/string_2/g;s/once/string_3/g;s/again/string_4/g' your_file;

the above command will do inplace replacement.if you want the ouput to console,then,
remove “i“.

another way is :

sed -e 's/hello/string_1/g;s/world/string_2/g;s/once/string_3/g;s/again/string_4/g' your_file

awk:

awk '{gsub(/hello/,"string_1");gsub(/world/,"string_2");gsub(/once/,"string_3");gsub(/again/,"string_4");print}' your_file