None of the non-<>-print solutions I see here will cope with a single opening blank line since they all search for multiple \n characters. This does the trick using the /m modifier, which allows ^ to match the beginning of a line anywhere in your string:

perl -p0777e 's/^\n+//mg'

In reply to Re: newlines in regular expressions by conrad
in thread newlines in regular expressions by gitarwmn

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