hi all In the system calls such as read,write.. the file system beneath only deals with the block number.. but how does the kernel map a position inside the file into a block number when the file is accessed..where does the code exist in which a file system specific request is made.. bye a Linux lover -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/