This is good, but the OP did say he wanted to remove the lines from a "large file", but your approach reads the entire file into an in-memory array (@lines) and processes that.

Check out my reply below for an example that loads only one line into memory at a time (the -n switch assumes while (<>)).

In reply to Re^2: Regex to remove data by rjt
in thread Regex to remove data by Anonymous Monk

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