And in a similar vein what would be the point of opening a file in read/write/truncate (w+) mode possibly be?

Yes, since w+ mode clobbers the file first, this is not usually a particularly useful mode. But a+ and r+ certainly do have their uses, for example, if you want any kind of random access to read/write the data in the file (e.g. updating fixed-length records) - though personally I've never done this directly, as this is usually the job of a library that handles that particular data format. However, see the last code example in my node here, in particular in combination with the notes on flock above it, this can be useful in some cases.

In reply to Re: What is the point of a+ and w+ when opening files? by haukex
in thread What is the point of a+ and w+ when opening files? by Maelstrom

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