Linked by Thom Holwerda on Wed 15th Jul 2009 16:09 UTC
Linux One of the problem with operating system updates is that you often need to reboot the system. While this is nothing but a minor nuisance for us desktop users, it's a bigger problem when it comes to servers. Ksplice is a technology that allows Linux kernel patches to be applied without actually restarting the kernel.
Thread beginning with comment 373820
To view parent comment, click here.
To read all comments associated with this story, please click here.
RE[4]: Already in NT.
by PlatformAgnostic on Fri 17th Jul 2009 01:20 UTC in reply to "RE[3]: Already in NT."
PlatformAgnostic
Member since:
2006-01-02

This is true in NT as well. But in UNIX the locking of files is advisory by default and shared by default (i.e. if I open a file anyone else can also open/modify the file and if I say I want to lock it other guys have to check the lock bit in order to respect my wishes). As a design choice (and to increase compatibility with older Windows), NT locking is mandatory and the default (if you specify no flags) is to disallow sharing. The library loader also seems to disallow sharing for delete as well.

As cetp mentions, this may be a conscious design choice because structures shared across process boundaries by DLLs (this can happen via things like Window Messages) may not tolerate having two different versions of the DLL loaded and interacting with each other. There's nothing in the NT Kernel architecture that prevents you from replacing a DLL when the program is still running (you can even do this yourself and get around the file locking problem by just renaming/moving the thing you want to replace and no one will stop you).

Reply Parent Score: 2