Well, there are a few obvious ways of doing so, one is to keep track of the last used number in a file or database, the other is to use a loop. Either over the files in the directory, keeping track of the highest number, or just start counting, stopping as soon as the corresponding file cannot be found.

However, the big question is, why?. This looks like a typical XY problem. You want to do X, and you think Y is the best way of doing so. Instead of asking about X, you ask about Y.

All of the methods I mentioned need some form of locking - lock the file, or make sure not two processes go searching for the "next" number. This might make your program more complex, and potentially slow. And that's in the probably relatively rare case of adding a new file. It looks like you will be getting a lot of files, and a single directory with a lot of files will mean accessing a file by name is going to be slow (linear search through the directory data block).

I don't know what you want to do with the files, but my gut feeling is shouting "shouldn't you use a database?".

-- Abigail

In reply to Re: sequencial file naming by Abigail
in thread sequencial file naming by Anonymous Monk

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