Agree with thanaz, it's shell dependent. 
sh -c "echo -e 'hi there'"
  -e hi there

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On some systems. Seems to be when dash (a simpler, faster shell), is used for sh instead of bash. 
bash -c "echo -e 'hi there'"
  hi there

/bin/echo -e 'hi there'
  hi there

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But why are you calling echo from perl in the first place? It's not necessary.

In reply to Re: which echo by ohcamacj
in thread which echo by dgillman

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