Hello Seth, I never intended to review all possible locking mechanism. In advisory I ment BSD-compliant flock()/fcntl()/open() file locking implemented in most unix-like systems. X/Open lockf() mechanism ported to few operation systems requires file to be open for writing, so, it's behind advisory (I'm talking about READ access). P.S. I don't use linux. --Saturday, December 08, 2001, 4:15:48 AM, you wrote to bugtraq@securityfocus.com: SA> On Fri, Dec 07, 2001 at 11:57:58AM +0300, 3APA3A wrote: >> The way file locks interfere with file access depends on OS. There are 2 >> possible situations: moderate and non-moderate file locks. *BSD and >> linux use non-moderate locking, while Windows NT locking is moderate. >> What does it mean? Under Unix file locking is only checked then another >> application tries to lock the file. If application doesn't use file >> locking it will not be affected by file locking. SA> 3APA3A -- close.... SA> A long-time feature of many Unix systems, including Linux (and probably SA> all the BSDs too, but I don't know this for sure) is mandatory file SA> locking, implemented in the kernel. It can be turned on using the setgid SA> bit on regular files. SA> Look for Documentation/mandatory.txt in the linux kernel source tree. It SA> has all the gory details on mandary file locking, as it is implemented SA> in the linux kernel. (Or, was implemented, in 1996.. :) SA> Cheers! -- ~/ZARAZA Ñýð Èñààê Íüþòîí îòêðûë, ÷òî ÿáëîêè ïàäàþò íà çåìëþ. (Òâåí)
