Please don't ignore requests to use <code> tags. You can edit your posts and add them. Having posted runnable code, the issues become more obvious: you open file "block.power" for writing, not reading--so use "<", not ">" (and you don't test whether the open succeeds). Your while loop loops infinitely over "$fh", which is always true; you should say while (<$fh>) {, which actually reads from the filehandle. The undefined variable in the pattern match is in fact $_.

In reply to Re^5: Extract lines between two patterns by philipbailey
in thread Extract lines between two patterns by mnithink

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