Not in general. I believe some operating systems / file systems support these kind of actions (when they use a record-based system for storing lines of text instead of using one large stream of bytes), but generally (at least on *nix and windows), the best you can do is write a new file and then move it over the original.

There are some perl modules that do what you describe, but they're generally not very efficient. See Tie::File for an example. For large files, you'd probably be better off using 2 files as described above.

"What should it profit a man, if he should win a flame war, yet lose his cool?"

In reply to Re: writing to a file by Joost
in thread writing to a file by Anonymous Monk

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