Re (tilly) 2: Planning a Disk CleanUp Script

A tip.

Use random integers, not sequential ones.

With sequential integers you have a race conditions. If 2 instances are trying to start at once, both can choose the same name and try to write to it, with bad results. Choose random integers and then test whether that one exists already and the odds of a bad race falls by several orders of magnitude.

Either that or have the integer in question produced by a single source, such as an autoincrement field in a database.

Comment on Re (tilly) 2: Planning a Disk CleanUp Script

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Re: Re (tilly) 2: Planning a Disk CleanUp Script by theguvnor (Chaplain) on Jan 15, 2002 at 07:41 UTC
Thanks for the tip tilly. You are right to suggest random integers for the reasons you have outlined. But I do want to point out that anyone writing such a system should also look to the security section in the Camel on race conditions, and also be sure to use `sysopen()` rather than relying on an file existence test and `open()`, for the reasons outlined in the Camel.	[reply] [d/l] [select]