NetBSD/usr.bin/file/magdir/compress

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#
# Formats for various forms of compressed data
# Formats for "compress" proper have been moved into "compress.c",
# because it tries to uncompress it to figure out what's inside.
#
# XXX - the two "packed data" versions are byte-swapped versions of
# one another; is that because the 2-byte magic number is written
# out in native byte order, with "unpack" figuring out the byte order
# from the magic number (in which case both can be left as is, or
# changed to specify a byte order *and* to indicate the byte order of
# the packing machine), or because the old "file" didn't have any way of
# having "magic"-file entries that specified a particular byte order?
#
0 short 017436 packed data
0 short 017037 packed data
#
# This magic number is byte-order-independent.
#
0 short 017437 old packed data
#
0 string \377\037 compacted data
0 short 0145405 huf output
#
# Squeeze and Crunch, from Keith Waclena <keith@cerberus.uchicago.edu>
# These numbers were gleaned from the Unix versions of the programs to
# handle these formats. Note that I can only uncrunch, not crunch, and
# I didn't have a crunched file handy, so the crunch number is untested.
0 short 0x76FF squeezed data (CP/M, DOS)
0 short 0x76FE crunched data (CP/M, DOS)
# Freeze
0 short 0x1f9f Frozen file 2.1
0 short 0x1f9e Frozen file 1.0
#
# GNU gzip compressor, from christos@deshaw.com (Christos Zoulas)
#
0 string \037\213 gzip compressed file method:
>2 byte <8 reserved,
>2 byte 8 deflate,
>3 byte &0x1f flags:
>3 byte &0x01 ascii-text,
>3 byte &0x02 multi-part,
>3 byte &0x04 name-present,
>3 byte &0x08 comment-present,
>3 byte &0x10 encrypted,
>4 ledate x last modified: %s,
>8 byte x extra-flags: %x,
>9 byte =0x00 os: MS/DOS
>9 byte =0x01 os: Amiga
>9 byte =0x02 os: VMS
>9 byte =0x03 os: Unix
>9 byte =0x05 os: Atari
>9 byte =0x06 os: OS/2
>9 byte =0x07 os: MacOS
>9 byte =0x0A os: Tops/20
>9 byte =0x0B os: Win/32