Besides the useless use of backticks pointed out in another subthread, this is also dangerous code:

`which perl` -x $0 $*
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What if I invoked this script as:

yourscript "randal l." schwartz
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I've just passed two parameters, but your reinvocation is going to give three parameters to the Perl program.

Quoting matters. The example in perlrun is very carefully constructed to avoid quoting problems.

-- Randal L. Schwartz, Perl hacker
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