What are device files...?? what are they used for?? and what are the differences between the two types CHARRCTER and BLOCK ?? Thank you !!

In Solaris all devices have 3 names depending on how referenced. Logical physical instance names Logical are used to refer to devices on the command line these are kept in /dev directory these are a symbolic link to the physical device name. examples are /dev/dsk/c0t0d0s1 etc or /dev/rdsk/c0t0d1s0. Physical device names identify the physical location of the hardware devices on the system and are maintained in the /devices directory. example when you do an ls on one of your disks it shows this as a symblic link to /devices/pci@lf,0/pci@1,1/ide@3/dad0,0:a This gives some info, that its an ide direct access device (dad) instance names are abbreviated names assigned by the Kernel. You can lsit the systems devices by catting /etc/path_to_inst. As the file says this is a critical file you shouldnt modify it The difference between block and character is how data is read/written to/from the target device. The access to a hard disk is in fixed blocks of 512bytes whereas other devices read invidiual characters. Of cse block devices begin with a b characters a c. Hope this was useful.

Thank you for your time JONOB!!!

Your very welcome!