It is bad karma to be writing a file that other processes are reading - you might get people who get part of the old file, and part of the new, and they probably wouldn't like that...

A better idead would be to write to a temporary file, and then, once the write is finished, rename the file to the name that the other processes use.

On most (all?) systems, those processes that have opened the old file will stil get to read the old file until they close it. But the processes that open the file after the rename, will get the new data. Best of all, you will have a guarantee that nobody will be reading a partialy-written file.

In reply to Re: Apache and file generation - flock? by matija
in thread Apache and file generation - flock? by ecuguru

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