The data is simple enough, a record per line. But there may be some lines that aren't valid records. I want to read only the first valid record and the last valid record without processing all the lines in between to see if they are valid. (Some files have over 1-million lines).

I have an idea how I might do it:

  • read from the top until I get to the first valid record.
  • seek the end of the file minus some reasonable block of bytes (figured from lines and bytes/line).
  • read the block until I get to the last valid record
  • if there aren't any valid records, back up one more, block, etc.

    It doesn't appear hard, but you never know.. and besides, I much prefer to use code that is alread written (lazy boat bum). Anyone know of a module that has this in it or working code? Or improvements on the algorithm? perlcapt

    In reply to Quick version of "first record" to "last record" ? by perlcapt

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