The (-i) switch is so easy for adjusting TEXT files. I use this so often, that in my login script, I set an alias for pie=perl -p -i~ -e. Easy as pie.

However, -i really doesn't edit "in place," but it does a good simulation of it. It creates a new file and moves the old file to a backup extension. You may have problems with access control lists (ACLs) on some network file system implementations. Experiment.

The '+' modes for the open() function are designed for fixed-record DATA updating. Note both examples in (perldoc -f open) refer to database files. Not that you couldn't use the functions for text files, but it would be a horrible and unnecessary tangle of seek(), tell() and caching to avoid overwriting parts of the next line before it is read. Not to mention further complications for newline conversion entanglement.

I wish the docs were more clear about this, to avoid this recurring question.

--
[ e d @ h a l l e y . c c ]

In reply to Re: In-place file manipulation by halley
in thread In-place file manipulation by ibanix

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