--- Om <omanakuttan@xxxxxxx> wrote: > Gaurav Dhiman wrote: > >>On Thu, 20 Jan 2005 04:55:20 -0800, Can Sar > >><csar@xxxxxxxxxxxx> wrote: > >> > >>>Hi, > >>> > >>>I wrote my own block device called sbd (using > code > > > > Minor numbers are NOT used to differentiate or > > recognize partitions, as you said. Actually there > are > I beg to differ. > Please refer to LDD, chapter 12, page 361. > Partitions are pulled based > on the minor numbers. yes I agree, but who is responsible for setting this minor numbers, I think its the block device driver. Kernel never uses the minor numbers. > > two device numbers, Major and Minor Numbers for > each > > device file. These numbers are associated with > each > > device file and they have a place in device file's > > inode. Major number is only important to the > kernel. > Based on the major numbers, system calls are > dispatched by kernel. This is surpurising to me ..... are you sure system calls are dispatched using major number. I think system calls have nothing to do with major numbers ..... whenever a system call is made, user process (actually library function) passes the system call number thru processor's registers and those system call numbers are totally different from major numbers of devices. You can find the system call number defined in architecture specific "unistd.h" file in kernel sources. System call numbers are defined as __NR_<syscall number> in "unistd.h" --gd ===== ------------------------------------------- Subscribe LKG_INDIA Group : Its Linux Kernel oriented group, started by bunch of guys from India. This group discusses the technical details of Linux Kernel, helping the members to share and enhance their knowledge on Linux Kernel and general OS concepts. Be a member of it if you are Linux Kernel Geek. For joining this group, mail to gauravd_chd@xxxxxxxxx Visit the LKG_INDIA home page: http://groups.yahoo.com/group/lkg_india/ ------------------------------------------- __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/
