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- ==========================
- = Split V1.00 =
- = =
- = (C) George Taylor 1994 =
- ==========================
-
- What is it?
- ===========
- 'Split' is a command line utility which splits files into many peices.
-
- Unlike other split utilities though there is no corresponding join utility,
- the resulting split files are 'self-joining' - a bit like self extracting
- archives.
-
-
-
-
- Copyright and disclaimer
- ========================
- This software is provided in good faith but there is no warranty.
-
- The author cannot accept any liability for any loss or damage resulting from
- the use in any way of this software.
-
- This software is FREEWARE. You may give copies to others provided they are
- unmodified and this document (with intact copyright notice) is included.
-
- The self-joining code created with split file is PUBLIC DOMAIN, it therefore
- does not effect any software licence which comes with software which you
- split using 'Split. You do not need to supply any copyright notice or
- this document with the self-joining code.
-
-
- How to split files
- ==================
- Use,
- Split <options>
- where options are:
-
- -f <filename> Specify input file. This option must be present.
-
- -n <name> Name of output file which is to be created when
- split pieces are joined together. This must not contain
- any path or directory components and is truncated
- to 19 characters. If this option is not present then
- the leaf name of <filename> is used.
-
- -o <output path> Output files to a particular path, otherwise
- the current directory is used. (Use dir. or path:
- for example).
-
- -s <split size> Size in K to split. The default is 128K.
-
- For example:
- split -f inputfile -n BigFile -o mydir. -s 50
-
- This will create files !BigFile, 01BigFile, 02BigFile etc. If the files already
- exist they are overwritten.
-
- The files xxBigFile can be recognised by the presence of GSTSPLIT in the
- first 8 bytes.
-
- The number is placed before the file name to ensure that there are no problems
- with long names being truncated.
-
- Note the resulting binary !BigFile is incapable of joining any files
- other than the ones generated at the same time !BigFile was generated.
-
- The !BigFile is public domain and you can give it away with your data files.
-
- How to join files
- =================
- 1 Ensure all the split files are in the same directory. It does not
- matter what the files are called or if there are other files in the
- same directory (including other split files). The filetypes don't
- matter either.
-
- 2 Double-click on the !BigFile file. All the parts of the original file
- will be joined together.
-
- 3 An error will be given if any parts can not be found or if the
- output file alreay exists. Note that files which do not have
- read access are skipped.
-
- 4 Assuming all was successful the original date-stamp and
- file type of BigFile are restored.
-
- 5 Finally assuming no errors the extracting program and data
- files are all deleted (if they are not locked).
-
- The joining program will start itself up in a taskwindow and multi-task
- if it can. No window is opened on screen though.
-
-
- Memory
- ======
- The joining process uses very little memory and will work within a
- 64K wimpslot (most of this space is used for file buffering).
-
-
- Reliability
- ===========
- CRC checks are calculated as follows:
- Splitting:
- (a) calculate CRC of input file
- (b) rewind input file
- (c) split input file
- (d) calculate CRC of join program
- Joining:
- (a) calculate CRC of join program
- (b) join files together
- (c) rewind output file
- (d) calculate CRC of output file
- (e) report warning if either CRC is incorrect
-
- This way errors in (i) the source disk, (ii) the transfer of files (eg ftp),
- (iii) splitting, (iv) joining (v), writing final file will be discovered.
-
- SWI OS_CRC is used to create CRC values.
-
-
- RISC-OS
- =======
- Split and the joining system have only been tested on RISC-OS 3.10. Later
- versions of RISC-OS will be fine, earlier versions I have not tested.
-
- The Shared C Library is required by both split and the joining system.
-