On Tuesday 04 May 2010 04:40:13 export@hope.cz wrote: > I have several running daemons that write some data to files > What happens with these open files when INIT 6 command is issued? Depends on the daemon. Prior to a clean reboot, a process is sent the TERM signal, which it may handle however it likes. Sometime later it is sent the KILL signal, which cannot be caught normally, and terminates the process. > Are these files that are used by daemons deleted? Or are they closed > regularly and saved ? When the kernel terminates the process, they are closed, but not normally. There's no C-language close() call or even a kernel-level "close" syscall. Any data in buffers above the file system layer are lost. > And what happens, if the Linux box is shut down in > a dirty way( out of electricity)? Thanks In this case, no software can really do anything, although things do happen for a few milliseconds. Any data in a buffer that doesn't have a battery is lost. Writes to disk that are in process my even get incorrect data. Depending on the file system(s) in use, recovery from this state should result in something like the kernel terminating every process with a KILL signal at some point *prior* to the power loss. -- Boyd Stephen Smith Jr. ,= ,-_-. =. bss@iguanasuicide.net ((_/)o o(\_)) ICQ: 514984 YM/AIM: DaTwinkDaddy `-'(. .)`-' http://iguanasuicide.net/ \_/
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