*Conan The Librarian
Formats and writes a label on a foreign mass storage volume. For directory-structured devices, the device directory is also initialized. Format INITIALIZE device-name [volume-label] INITIALIZE/CREATE file-name [volume-label]
|1 - Parameters|
device-name Specifies the name of the device on which the volume to be initialized is physically mounted. The device name can also refer to the name of a mounted virtual device to be reinitialized. file-name For INITIALIZE/CREATE, file-name refers to the name of a file to be created and initialized as a virtual device. volume-label Specifies the identification to be written onto the volume header for RT-11 volumes only. The volume label can contain up to a maximum of 12 alphanumeric characters. The default is OpenVMS Exchange. Use quotation marks to specify a volume label with lowercase letters.
|2 - Description|
The EXCHANGE command INITIALIZE erases all files from a volume. After initialization, the volume directory contains no files. DOS-11 magnetic tapes and RT-11 block-addressable devices can be initialized. The device must be mounted with the /FOREIGN qualifier.
|3 - Qualifiers|
3.1 - /ALLOCATION
/ALLOCATION=n Specifies the allocation of a new virtual device file in terms of 512-byte blocks. The allocation specified is the number you entered as n. If you do not specify the /ALLOCATION qualifier when you create a new virtual device file, the default allocation is 494 blocks, the size of a single-density diskette. The maximum allocation is 65,536 blocks. A virtual device file is usually the size of a standard device supported by both RT-11 and OpenVMS. These sizes are as follows: Device Blocks TU58 512 RX01 494 RX02 494 (single density) RX50 800 RX02 988 (double density) RX33 2400 RL02 20480 RK06 27126 RK07 53790 You can also use the /ALLOCATION qualifier to reduce the size of a physical device. For example, if you want to prepare an RL02 disk but have only an RK07 device available, you can initialize the RK07 to a volume of 20,480 blocks. When the RL02 is available, you can transfer the files to the RL02 knowing they will fit on the smaller device.
3.2 - /BADBLOCKS
/BADBLOCKS[=RETAIN] Performs a bad block scan of the volume before initialization. A file named FILE.BAD is created on top of each bad block or group of bad blocks encountered on the device, preventing any future use of the bad areas. If a bad block is found in either the boot block or the volume directory, the volume is not usable and EXCHANGE displays an error message. If the bad block is in a directory segment other than the first, you might be able to use the volume by reinitializing it with a smaller number of segments (see the /SEGMENTS qualifier description). If you specify /BADBLOCKS=RETAIN, EXCHANGE uses the device's existing bad block information, instead of performing a bad block scan. Therefore, initializing takes less time. If you do not specify RETAIN, EXCHANGE writes a pattern on each block of the volume, then reads each block to verify that the block is usable. EXCHANGE prints a list of the bad blocks found on the device. RK06, RK07, and RL02 disk volumes support bad block replacement. Therefore, HP recommends that you use the /REPLACE=RETAIN qualifier for these volumes. If you use the /BADBLOCKS qualifier with a volume initializied previously with the /REPLACE qualifier, EXCHANGE deletes the bad block replacement table and performs a new bad block scan. If you use /BADBLOCKS=RETAIN with such a volume, EXCHANGE uses the FILE.BAD files created during the volume initialization.
3.3 - /CREATE
Specifies that a virtual device is to be created and initialized. The specification is a file name; if a file type is not given, EXCHANGE applies the default type of DSK.
3.4 - /DENSITY
/DENSITY=density-value Specifies, for magnetic tape volumes, the density in bytes per inch (bpi) at which the tape is to be written. For magnetic tape volumes, the density value specified can be 800 or 1600, as long as the density is supported by the magnetic tape drive. If you do not specify a density value for a blank tape, the system uses a default of the lowest density supported by the tape drive. For the RX02 dual-density diskette drive, use the DCL command INITIALIZE/DENSITY=SINGLE or INITIALIZE/DENSITY=DOUBLE to reformat the diskettes to a different density; then use the EXCHANGE command INITIALIZE to create the RT-11 directory structure. NOTE Diskettes formatted in double density cannot be read or written by the console block storage device (an RX01 drive) of a VAX-11/780 until they have been reformatted in single density.
3.5 - /EXTRA_WORDS
/EXTRA_WORDS=n Specifies, for RT-11 volumes, the number of extra words to add to each directory entry, in addition to the required seven words. The ability to increase the length of directory entries is useful for some RT-11 applications. Increasing the size of the directory entries reduces the number of entries that fit in each directory segment.
3.6 - /MESSAGE
/MESSAGE /NOMESSAGE Controls whether or not EXCHANGE displays a message that the volume was initialized. The default is determined by the /MESSAGE qualifier entered with the EXCHANGE command when EXCHANGE was activated.
3.7 - /REPLACE
/REPLACE=RETAIN Retains, when an RT-11 volume is initialized, the bad block replacement table and any existing FILE.BAD files. The RETAIN option is required; EXCHANGE cannot build a replacement table for a volume. The RT-11 system builds and uses the table based on specific hardware error conditions. The OpenVMS I/O system is different, and cannot be relied upon to generate exactly the same error conditions. Therefore, it is not possible for EXCHANGE to generate the same replacement table that would be generated by RT-11. If no replacement table is present, the qualifier /REPLACE=RETAIN is equivalent to /BADBLOCKS=RETAIN.
3.8 - /SEGMENTS
/SEGMENTS=n Defines, for RT-11 volumes, the number of 2-block directory segments to allocate for the directory. The number of segments in the directory establishes the number of files that can be stored on a device. The system allows a maximum of 72 files per directory segment and 31 directory segments per device. The argument n represents the number of segments; the valid range for n is from 1 to 31 (decimal). The default values for n depend on the device type, as follows: Device Segments TU58 1 RX01 1 RX02 1 (single density) RX02 4 (double density) RX50 4 RX33 16 RL02 16 RK06 16 RK07 31
3.9 - /VOLUME_FORMAT
/VOLUME_FORMAT=option Defines the physical format of the volume to be processed. The EXCHANGE command INITIALIZE is not valid for Files-11 devices.
|4 - Examples|
1.$ MOUNT/FOREIGN DLA2: %MOUNT-I-MOUNTED, mounted on DLA2 $ EXCHANGE EXCHANGE> INITIALIZE DLA2: %EXCHANGE-S-INITIALIZED, the RT-11 volume _DLA2: has been initialized The command in this example initializes the volume mounted on the RL02 drive DLA2. Since DLA2 is a block-addressable device mounted with the /FOREIGN qualifier, RT-11 is the default format. EXCHANGE physically scans all blocks of the volume, builds a bad block replacement table, and displays a message indicating that it failed to turn up any bad blocks. 2.EXCHANGE> INITIALIZE MTA0:/DENSITY=1600 The command in this example initializes the DOS-11 magnetic tape volume loaded on MTA0. The density is specified as 1600 bpi; the default would have been 800 bpi for an MT drive. 3.EXCHANGE> INITIALIZE/CREATE/ALLOCATION=1000 VIRTUAL %EXCHANGE-S-INITIALIZED, the RT-11 volume DRB0:[LOGIN]VIRTUAL.DSK has been initialized The command in this example creates a virtual device with an allocation of 1000 blocks in the directory [LOGIN] on DRB0. EXCHANGE applies the default file type DSK.