Now if I need to go back to a particular line say line number 30 ...how do I do it if I have already passed this line.

There are two approaches.

  1. Read the entire file into memory. (E.g., as an array of lines.) You get rapid access to arbitrary lines.

    my @lines = <FILE>; will read from an open file handle into an array.

  2. If the file can't fit in memory (or you choose not to read it all in at once), use tell() to remember interesting places, and seek() to get you back there. They're covered in perlfunc.

Update: tilly pointed out that it's also possible to re-read the file. You can do that by closing and reopening the file (which assumes that the file hasn't been rewritten in the interim), or you can rewind the file handle.

In reply to Re: FILE operation in PERL by dws
in thread FILE operation in PERL by ramesh_nathan

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