Steven Solie: /* SPLT */

2012-05-10T20:01:01Z

SPLT

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	ASDG's File SPLiTting system		ASDG's File SPLiTting system

Steven Solie: Created page with "= SPLT = ASDG's File SPLiTting system Here is the IFF SPLT Form. It is intended to provide a way to split big files into smaller pieces. I am developing program to r..."

2012-05-10T20:00:51Z

Created page with "= SPLT = </pre> ASDG's File SPLiTting system Here is the IFF SPLT Form. It is intended to provide a way to split big files into smaller pieces. I am developing program to r..."

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= SPLT =

</pre>
ASDG's File SPLiTting system

Here is the IFF SPLT Form.
It is intended to provide a way to split big files into
smaller pieces. I am developing program to read/write this
format on a variety of platforms. Currently I have Amiga
and MSDOS versions.

It could also be used to encapsulate binary files.

Also, my program generates, and expects, SPLT file names of the form
"name.001", "name.002". This oughta be part of the specification for this
format, although such details are beyond the scope of IFF.

FORMnnnnSPLT
Chunk types:
INFOnnnn Information about the data file
total_size Total size of original file **
count Total number of chunks. **
position Position this chunk was in original file
This is defined bye:
"Seek(file, position, OFFSET_BEGINNING)"
unit_number Number of this chunk, from 0..(count-1)
secs UNIX date format, seconds since Jan 1 1970
AmigaDOS Seconds + 252482400 == UNIX Seconds.
bits File mode bits...defined by AmigaDOS
compression Compression type for the BODY chunk
Compression types can be different for
each BODY chunk.
No compression types are defined yet.

EOF 0004
flag either TRUE or FALSE.
CHKS0004
sum The sum of the data in this chunk
Sum the data chunk, a byte at
a time. For example:

long sum = 0;
UBYTE *p = buffer;

for(i=0;i<length;i++) sum += *p++;

TYPEnnnn
type Mac filetype info. As yet this is
not clearly defined. I will further define
this when a Mac port is done. RSN
NAMEnnnn
chars The original filename. Do not depend on NULL
termination.
BODYnnnn
.. The actual data for this chunk

The INFO chunk MUST appear before the BODY chunk. Also, the NAME chunk has
to appear before the BODY chunk in the first file in order to be useful.
The NAME chunk is not required.

The EOF chunk is not required except as noted below.

Note that the unit number in the INFO chunk start numbering things at
zero, but my SPLT writer writes files with names starting at 001.

** The totalsize and count fields may be zero. If this is the case then
the file size and or chunk size could not be known ahead of time. Readers
of this FORM should expect this. The last file in a sequence MUST then
have an EOF chunk with contents of TRUE. If a file has a true EOF chunk,
then the data section MAY be missing. If the last file (with total_size ==
0) did not contain an EOF, with flag TRUE, chunk then the end of the data
file is missing.

-- joe porkka, ASDG Inc.
(608) 273 6585
</pre>

SPLT IFF File Splitting - Revision history

Steven Solie: /* SPLT */

Steven Solie: Created page with "= SPLT = ASDG's File SPLiTting system Here is the IFF SPLT Form. It is intended to provide a way to split big files into smaller pieces. I am developing program to r..."