From the perlman:perlvar page 
Works like awk's RS variable, including treating empty
lines as delimiters if set to the null string.
...
You may set it to a multi-character string to match a
multi-character delimiter, or to undef to read to end of
file.

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The values of '' and undef both have pre-defined meanings in the context of the $/ variable.

In reply to Re: Altering the value of by plaid
in thread Altering the value of "$/" by greenhorn

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