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env variables

 
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Hi All,

Does anyone know how to check if a environment variable is set or not from inside a perl script?

- Preethi
 
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Perl has a special associative array created by default, called ENV. So, if you want the PATH, you can do this:

If you want to see a list of all your variable and their values, a loop would look like this:

to see if it's defined or not, just test it:
 
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There is an exists() function that can be applied to any associative array. For example to check for the existence of a particular environment variable :-


Just checking the value $ENV{"SOME_NAME"} will not tell you if the environment variable is set since the result will be the same for not set as for it being set but empty. Does the distinction matter to you? If not then just get the value and test it. If so then use exists().
 
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