ABOUT CORELCDX VERSION 1.0 ========================== The following syntax shows all the switches available for the CorelCDX statement: CORELCDX /D: /M: /L: /E /FILES: /CACHE:;; /DATABLK: /E: /STACK [:] Note: The installation adds the default CorelCDX statement to your AUTOEXEC.BAT file. However, if you've already installed MSCDEX, the installation adds the CorelCDX code to your system, but doesn't replace MSCDEX in your AUTOEXEC.BAT file. SUPPORTED MSCDEX COMMAND LINE SWITCHES -------------------------------------- The following MSCDEX command line switches are compatible with CorelCDX version 1.0. /D: -- identifies the name of the CD-ROM device driver to be used. You can enter more than one /D: switch to identify multiple CD-ROM device drivers. Names you enter must match names used in the /D: parameters for each device driver entry in the CONFIG.SYS file. /M: -- specifies the approximate number of sector buffers allocated. Using a predetermined formula, the total number of sector buffers is divided among the path table, directory, and data cache. Minimum, maximum, and alignment requirements may require that the actual number of buffers may differ slightly from those you specify. See the related discussion about the /CACHE switch. /L: -- forces CD-ROM drive letter assignment to begin at a particular drive letter if you have software that requires that your CD-ROM drive be assigned a specific drive letter. If that drive letter is not available, CD-ROM drives are assigned from the next available drive letter. /E -- uses expanded memory for the cache buffers if it's available. Expanded memory is allocated in blocks. To make the most efficient use of allocated memory, this switch may slightly increase the number of specified cache buffers. See the related discussion about the /E: switch. EXTENDED CORELCDX COMMAND LINE SWITCHES --------------------------------------- The following command line switches are specific to CorelCDX. /FILES: -- specifies the number of CD-ROM files that you can open at the same time. Each file requires approximately 16 bytes. By default, the limit is the number specified by the FILES= line in the CONFIG.SYS file. /CACHE:;; -- specifies the number of cache blocks to allocate for the path table cache, directory cache, and data cache. Each block requires 2K. The path table cache stores information about the name and location of each sub-directory on the CD. Each (2K) path table cache buffer accommodates approximately 100 sub-directories. The directory cache stores information such as the name and location of the files in each sub-directory on the CD. The data cache stores the most recently accessed contents of files on the CD. When you specify the number of sector buffers using the /M: switch, the value is divided among the path table, directory, and data cache using a predetermined formula. You can use the /CACHE:;; switch to fine-tune the allocation of cache blocks. When adjusting the allocation of cache blocks, you can't exceed the following minimum and maximum sizes for each area. path table cache: block size= 1 sector min= 2 sectors max= 64 sectors directory cache: block size= 1 sector min= 2 sectors max= 64 sectors data cache: block size= 2 sectors min= 1 block (If you use /DATABLK to alter the block size, the minimum sectors change.) max= 64 sectors When using expanded memory for cache buffers, certain internal alignment requirements are enforced. You can't change these requirements. Note: The /CACHE: and /M: switches are mutually exclusive. If you use both switches, the /M: switch is ignored. /DATABLK: -- adjusts the number of 2K sectors assigned to each data cache block. Valid values are 1, 2, 4, or 8. The default is 2. This option is useful for applications that read data from a CD in contiguous segments. CorelCDX uses a read ahead plus least recently used (LRU) algorithm for its data cache. Data read into the cache is read in blocks. Setting the data block size to 1 disables read-ahead caching, but an additional 4K of conventional memory is required. Also, note that the read-ahead caching logic internal of some CD-ROM drives is adversely affected by changing the default data cache block size. /E: -- extends the basic MSCDEX compatible /E switch by allowing you to force CorelCDX to use expanded memory, if it's available, for code, data, or cache buffer storage. The valid options are: 1 = code/data ONLY in expanded memory 2 = cache blocks ONLY in expanded memory, the same as /E switch 3 = code/data AND cache blocks in expanded memory When expanded memory is used for code and data, only a small 'foot-print' (less than 2K) remains resident in conventional memory. This option may be incompatible with some CD-ROM applications; for example. those that perform absolute disk reads into expanded memory buffers. If cache buffers are located in expanded memory, a small amount of conventional memory may also be allocated for storage of required tables. Also, to make efficient use of expanded memory, and due to internal cache alignment requirements, the number of cache blocks in use may be adjusted slightly when this option is used. /STACK [:] -- causes CorelCDX to switch to its own internal stack while processing software interrupts, rather than using the calling programs stack. Use the variable to change the stack from its default size of 512 . For example, /STACK:1024 causes a 1K stack to be used, while /STACK:256 causes a 256 byte stack to be used. UNSUPPORTED MSCDEX COMMAND LINE SWITCHES ---------------------------------------- The following MSCDEX command line switches are not supported under CorelCDX version 1.0. /V - verbose mode to display information during boot up /S - patch to allow sharing of CD-ROM drives on MS-NET based servers /K - force selection of shift-JIS Kanji Supplemental Volume Descriptors