The basic problem is that for most commonly used filesystems there basically is no API to remove things from the front (or the middle). Modules like Tie::File only help in the sense that they do things in a smarter way than just an array read and write, but they still work by basically rewriting everything after your deletepoint.

So if you do this kind of stuff on small files, Tie::File is a fine solution. If the files get big, you'd better rethink your storage format. E.g. use multiple files with a given maximum size, or use a dbm file, or go for a SQL database or so. Or if you don't mind that old data remains in the file, simply have a companion file that remembers the seek position of where you got last time, or even have this data in a fixed size record at the start of your file (there are ways to overwrite a range of bytes with the same amount of (different) bytes.

In reply to Re: Shifting the top line(s) of a file? by thospel
in thread Shifting the top line(s) of a file? by Cody Pendant

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