<?xml version="1.0" encoding="utf-8"?>
<PRONOM-Report xmlns="http://pronom.nationalarchives.gov.uk">
  <report_format_detail>
    <FileFormat>
      <FormatID>1256</FormatID>
      <FormatName>MS DOS Compression Format (KWAJ Variant)</FormatName>
      <FormatVersion>
      </FormatVersion>
      <FormatAliases>
      </FormatAliases>
      <FormatFamilies>
      </FormatFamilies>
      <FormatTypes>
      </FormatTypes>
      <FormatDisclosure>
      </FormatDisclosure>
      <FormatDescription>The MS-DOS compression format uses the LZSS algorithm to compress a single file into another single file, 
replacing the last character in the filename with an underscore. It is implemented via the MS-DOS commands COMPRESS.EXE and EXPAND.EXE.</FormatDescription>
      <BinaryFileFormat>
      </BinaryFileFormat>
      <ByteOrders>
      </ByteOrders>
      <ReleaseDate>
      </ReleaseDate>
      <WithdrawnDate>
      </WithdrawnDate>
      <ProvenanceSourceID>1</ProvenanceSourceID>
      <ProvenanceName>Digital Preservation Department / The National Archives</ProvenanceName>
      <ProvenanceSourceDate>25 Oct 2012</ProvenanceSourceDate>
      <ProvenanceDescription>
      </ProvenanceDescription>
      <LastUpdatedDate>04 Mar 2022</LastUpdatedDate>
      <FormatNote>A DOS compressed file will be named file.**_, so a .exe will look like file.ex_, a DOS compressed .jpg will look like file.jp_ etc.

https://www.cabextract.org.uk/libmspack/doc/szdd_kwaj_format.html</FormatNote>
      <FormatRisk>
      </FormatRisk>
      <TechnicalEnvironment>
      </TechnicalEnvironment>
      <FileFormatIdentifier>
        <Identifier>fmt/469</Identifier>
        <IdentifierType>PUID</IdentifierType>
      </FileFormatIdentifier>
      <InternalSignature>
        <SignatureID>733</SignatureID>
        <SignatureName>MS DOS Compression format (KWAJ)</SignatureName>
        <SignatureNote>BOF: KWAJˆð'Ñ</SignatureNote>
        <ByteSequence>
          <ByteSequenceID>922</ByteSequenceID>
          <PositionType>Absolute from BOF</PositionType>
          <Offset>0</Offset>
          <MaxOffset>
          </MaxOffset>
          <IndirectOffsetLocation>
          </IndirectOffsetLocation>
          <IndirectOffsetLength>
          </IndirectOffsetLength>
          <Endianness>
          </Endianness>
          <ByteSequenceValue>4B57414A88F027D1</ByteSequenceValue>
        </ByteSequence>
      </InternalSignature>
    </FileFormat>
    <SearchCriteria>Criteria</SearchCriteria>
  </report_format_detail>
</PRONOM-Report>
