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- 笊絶武笊 1. Introduction 笊絶武笊
-
- SaveDskF.exe and LoadDskF.exe are a pair of utilities to save a diskette to a
- file and vice-versa. These programs are not intended to save fixed disk images.
- They have these characteristics:
-
- o Run under OS/2 and DOS 3.3 or later.
-
- o Empty sectors above the highest occupied sector are not included in the file.
-
- o The data may be compressed.
-
- o Diskettes may be formatted as they are written.
-
- o Standard diskette formats are supported.
-
- o Conversion to a larger diskette image is possible.
-
- o Label text may be included in the file that is displayed by LoadDskF before
- the diskette is written.
-
- o The progress of the data transfer is visible on the screen.
-
- o Built-in Checksum function.
-
- o Handles "image" files generated by other programs.
-
- Efficient portability of complete diskette images is provided for transmission
- via data networks. Boot, file allocation table, directory and data sectors are
- included. Both programs provide a short help facility when some types of syntax
- errors are detected. Just type the program name to get help.
-
-
- 笊絶武笊 2. LoadDskF 笊絶武笊
-
- The calling syntax is:
-
- LoadDskF [D:][path]filename.dsk d: [/F][/C][/Y][/Q]
-
- The diskette image contained in the file is written to the specified target
- drive d:. The target diskette must have the same format as the original
- diskette. If the format is incorrect, an informational message indicates the
- required format.
-
- A warning message appears before the data transfer begins so that syntax errors
- do not result in a corrupted diskette. It is necessary to press the "y" key in
- order to continue the process. A return code of 31 (decimal) is issued if the
- response is not "y". Alternatively, /Y will bypass the need to press the "Y"
- key. When both /Y and /Q are invoked, the warning message is omitted.
-
- In the event of a checksum error, both the expected and calculated values are
- displayed.
-
-
- 笊絶武笊 3. Image files 笊絶武笊
-
- Loaddskf supports input files that represent a pure binary image of the disk
- that has been generated by SaveDskf with the /D and /A options or other
- programs, such as DSKIMAGE and DISKIMGE. Image is defined as the uncompressed
- disk data without header or trailer. The file must be the exact size of a
- standard diskette. Diskettes supported are 1.44M, 1.2M, 720K and 360K.
-
-
- 笊絶武笊 4. Formatting 笊絶武笊
-
- When /F is specified, each track is formatted before it is written. When all of
- the data has been written, LoadDskF continues to format the remainder of the
- tracks.
-
-
- 笊絶武笊 5. Converting a Diskette 笊絶武笊
-
- When /C is specified, the diskette image can be written on a diskette of a
- different format than the original diskette provided that it is at least as
- large as the original. The resultant diskette's capacity will then appear to
- have the original diskette's capacity. After executing LoadDskF /C, it is
- recommended that the files be transferred to another diskette using the DOS
- copy command. The diskette with the truncated capacity should then be
- reformatted.
-
- When you use the /C option together with the /F option, your diskette will be
- formatted to the highest density supported on the drive (not exactly true, but
- it will be most of the time). There is no means for specifying lower capacity
- media. The image written to diskette will be logically the same as the source.
- There are some subtle differences, however. Let's assume that we have a 1.2Mb
- image that we want to put onto a 1.44Mb diskette. There are 18 sectors per
- track on a 1.44Mb diskette. There are only 15 on a 1.2Mb diskette. In this case
- we would only write 15 of the 18. The boot record would tell us that there were
- only 15 sectors per track. This looks to DOS just as if it were a real 1.2Mb
- diskette. Physically, there are actually 3 sectors on each track that are not
- used. DOS is told they don't exist and it never looks for them.
-
- When you tell LoadDskF the /F option, it will format the output diskette to the
- same density as the input diskette image (providing, of course, that the
- diskette drive supports that kind of image).
-
- If you ALSO use the /C option, your diskette will be formatted to the highest
- density that the drive supports. If we assume we have a 2.88Mb diskette drive
- and a 1.2Mb or 1.44Mb diskette image, the diskette will be formatted to 2.88Mb.
- The image written to diskette will be either 1.44Mb or 1.2Mb. It will
- PHYSICALLY be formatted as 2.88Mb, but will LOGICALLY be a 1.44Mb or 1.2Mb
- diskette. If you first wrote the 1.44Mb image to a diskette and then used ONLY
- the /C option and wrote a 1.2Mb image to the same diskette, it would work. If
- you now try to write a 1.44Mb image to the same diskette with only the /C
- option, it would fail. This is because DOS thinks that you have a 1.2Mb
- diskette in the drive and a 1.44Mb diskette won't fit. In this case, you MUST
- use both the /C option and the /F option.
-
- It is important to understand that this is not an all encompassing conversion
- from 3.5 to 5.25 inch media. In some instances, 3.5 inch media is provided for
- PS/2 systems and 5.25 inch media for PC systems. Therefore code that supports
- hardware may be different for each media type.
-
- In those cases where the media type is unimportant, a file packager such as
- SaveRam or PKZIP is strongly recommended over SaveDskF so that those who
- receive the packed file need not have a particular type of diskette drive.
-
-
- 笊絶武笊 6. Progress Indication 笊絶武笊
-
- As the data is written to the diskette, the percentage of the data which has
- been written is displayed on the screen. If the diskette is being formatted as
- it is written, the percentage is based on the diskette capacity.
-
-
- 笊絶武笊 7. DOS Compatibility Mode 笊絶武笊
-
- There is sometimes a problem when operating in the DOS compatibility mode where
- DOS does not recognize the newly generated diskette. When this happens, the
- diskette appears to have incorrect system information and it is necessary to
- partially remove it and re-insert it in the drive.
-
-
- 笊絶武笊 8. Up/Down loading 笊絶武笊
-
- When transferring diskette image files between the PC and a host system, it is
- necessary to treat them as binary files, i.e. no translation of data must
- occur. If the file data has been translated, LoadDskF will usually give an
- error message indicating that the file is not compatible with LoadDskF.
-
- It is also necessary to download any executable file including LoadDskF.exe and
- SaveDskF.exe as binary files without translation. When translation occurs, the
- results are unpredictable and usually hang the machine requiring a power off/on
- sequence to get back into operation.
-
- LoadDskF will ignore any data at the end of a file that is shorter than a
- complete sector. This provides some forgiveness for the common error of
- uploading to a fixed record length file on a host system which results in a
- meaningless string of data at the end of the file which is usually not longer
- than 80 bytes.
-
-
- 笊絶武笊 9. SaveDskF 笊絶武笊
-
- The calling syntax is:
-
- SaveDskF d: [D:][path]filename.dsk [/D][/A][/N][/M][/K]
-
- Since the diskette that the file will be copied to by LoadDskF must be the
- identical format as the original, it may be helpful to give the file a name
- that is indicative of the required format, e.g. DOS4028.DSK to indicate 40
- tracks, 2 sides and 8 sectors per track. An extension of .DSK is recommended
- to indicate a diskette image file.
-
- The complete image of the diskette in drive d: is written to the specified
- file. A file header as described below and all diskette sectors are written up
- to and including the highest occupied data sector. Whether or not a data
- sector is in use is determined from the file allocation table. An informational
- message is displayed if some of the sectors written do not actually contain
- data. This means that there are some gaps in the data portion of the diskette.
- An appropriate response is to run a disk defragmentation program against the
- source diskette. Copy protected diskettes having non-standard sector numbers
- cannot be saved by SaveDskF. Only standard DOS formats are supported.
-
- As the data is written to the file, the percentage of the data which has been
- written is displayed on the screen.
-
-
- 笊絶武笊 10. Pure Diskette image 笊絶武笊
-
- The /D option omits the file header and inhibits compression of the diskette
- data. The resulting file is intended for use with diskette copying software
- and is not compatible with LoadDskF.exe unless the /A option is also used. When
- /D is specified, /K and /M will generate an error message.
-
-
- 笊絶武笊 11. Save Entire Disk 笊絶武笊
-
- The /A option saves the whole diskette regardless of the data stored on it.
-
-
- 笊絶武笊 12. Data Compression 笊絶武笊
-
- The /N option inhibits data compression. This is useful when the compression
- algorithm fails and produces data that is larger than the uncompressed data.
- When this happens, SaveDskF displays an informational message recommending that
- you rerun the program with /N specified.
-
-
- 笊絶武笊 13. Commentary message 笊絶武笊
-
- The /M option tells SaveDskF to get text from the specified file to be included
- as a comment in the diskette image file which LoadDskF will display before
- unloading the diskette data. It may contain information on any aspect of the
- diskette usage or the way it is to be unloaded. This provides a means of
- ensuring that the recipient of the diskette will be aware of important
- information.
-
- The /K option allows you to type in a brief commentary message on the command
- line. The text must follow immediately and be enclosed in either single or
- double quotes. The entire command length is limited to 128 bytes. When enclosed
- in single quotes, double quotes may be used in the text and vice versa. If a
- message file has been specified with /M, the /K text is added to its contents.
- The total length of the message may be up to 4096 bytes except when /C is used.
- In that case, the message length may be up to 470 bytes.
-
- Examples of these flags are:
-
- SaveDskf a: test.dsk /k"This is a 1.44Mb diskette"
- OR
- SaveDskf a: test.dsk /mtest.msg
- OR
- SaveDskf a: test.dsk /m test.msg
- Where test.msg might contain:
- +--------------------------+
- + This file could contain +
- + the text that you would +
- + want printed on the label+
- + of the diskette. +
- +--------------------------+
-