How about

  1. Open the file.
  2. Read until the first valid record is reached. That's your First Record.
  3. Reopen the file with File::ReadBackwards.
  4. Read until the first valid record is reached. That's your Last Record.

I've never used the module, but someone who did once praised it here on Perl Monks. Also, the docs say it's "memory efficient", so it doesn't read the whole file into memory.

In reply to Re: Quick version of "first record" to "last record" ? by ikegami
in thread Quick version of "first record" to "last record" ? by perlcapt

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