fdisk System Maintenance fdisk Change hard disk partitioning /etc/fdisk [-r] [-c] [-b mboot] xdev The command fdisk supports flexible hard-disk partitioning among various operating systems (e.g. MS-DOS, CP/M, COHERENT, and XENIX). This capability means that up to four operating systems can be supported on one hard disk. fdisk recognizes the following flags: -r Read-only access to partitioning information. -b Use the first 446 bytes of mboot as master boot code to replace that in xdev. -c Allow the specification of disk geometry (i.e. number of cylinders, heads, sectors) for disk drives which are not sup- ported by the system BIOS. fdisk accesses the first block from the special device xdev (e.g., /dev/at0x) for the partitioning information. fdisk then queries the user for changes. These changes are written to xdev only if the user requests the changes to be saved. ***** Files ***** <fdisk.h> ***** See Also ***** system maintenance ***** Notes ***** If the partition table is changed, the system should be rebooted; most device drivers will not recognize the revised partition in- formation until a reboot occurs. As the -r and -b options are contradictory, attempting to use them together generates an error message. Please note that some versions of fdisk for other operating sys- tems can rearrange the order of entries in the partition table. If this happens, you may lose the ability to run COHERENT until the table is restored to its previous order. A sign of this problem is getting the prompt AT boot? when trying to start COHERENT after running any fdisk program, and not being able to get past it. COHERENT Lexicon Page 1