diotalevi explained the reason, let me just provide the corrected code:
while (($_=<FH>) !~ /^\"\@ENDQUERY\"/) {

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(Note that this code will get into trouble if there is no @ENDQUERY at the end of the file...

In reply to Re: $_ and nested while loops w/angle operator by matija
in thread $_ and nested while loops w/angle operator by alienhuman

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