CODEWITHSUNDEEP
perlshell
dicaprio
dicaprio

Reputation: 733

How do we replace PATH in all the files with an env variable

I have around 230 files which are *.pl , *.txt and some are *.conf files which has a default path set to the current environment say /home/AD/USR/perl/5.8.0/bin/perl. I need to replace "/home/AD/USR" with an environment variable ${USR_PATH}. The files I want to modify are in subdirectories. Which means my script should find e.g find .|xargs grep -l "/home/AD/USR" all the files and then replace the string.

Can some one give me a clue how do I do that?

Shell : /bin/bash Env : Linux x86_64

Upvotes: 1

Views: 1842

Answers (2)

TLP
TLP

Reputation: 67900

If you replace part of a string with ${USR_PATH} you will refer to the perl variable $USR_PATH, not the environment variable, which is in perl referred to as $ENV{USR_PATH}.

perl -pi.bak -we 's#/home/AD/USR(?=/perl/5.8.0/bin/perl)#\$ENV{USR_PATH}#g' 
    *.pl *.txt *.conf

Using the lookahead will save you the trouble of replacing the rest of the path afterwards.

I assume you want to replace it with the literal value. If you want to replace it with the actual value in the environment variable, just remove the backslash in front of $ENV.

While using an environment variable seems handy and all, it will reduce your scripts portability. Why not use a configuration file? If you had done that from the start, you wouldn't be having this trouble. Search CPAN for a nice module.

Upvotes: 1

swingbit
swingbit

Reputation: 2745

perl -i -pe 's|/home/AD/USR/perl/5.8.0/bin/perl|\${USR_PATH}/perl/5.8.0/bin/perl|' <your files>

Upvotes: 1

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