[Chapter 8] 8.46 Env
Author: Ellen Siever, Stephen Spainhour & Nathan Patwardhan
Date: 1999-07-02T01:45:04Z

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| Chapter 8 Standard Modules |

## 8.46 Env

Lets your program treat environment variables as simple variables instead of having to access them from the `%ENV` pseudo-hash where they are kept.

>     use Env;

>     use Env qw(var1 var2 ...);

Internally, Env uses an `import` function that ties suitably named environment variables to global Perl variables with the same names. By default, it ties all variables yielded by `keys %ENV`. A "suitable" environment has a name that begins with an alphabetic character and contains only alphanumeric characters or underscores.

When `use Env` is invoked with arguments, the arguments are interpreted as a list of environment variables to `tie`, but the variables don't have to exist yet. After a variable has been tied, you can use it like a normal variable, accessing or changing its value.

You untie a variable by setting its value to `undef`.

8.45 English |  | 8.47 Errno