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-rw-r--r--usr.bin/file/magdir/compress42
1 files changed, 20 insertions, 22 deletions
diff --git a/usr.bin/file/magdir/compress b/usr.bin/file/magdir/compress
index 702eb68cb81..2cf8d195f59 100644
--- a/usr.bin/file/magdir/compress
+++ b/usr.bin/file/magdir/compress
@@ -2,7 +2,7 @@
#------------------------------------------------------------------------------
# compress: file(1) magic for pure-compression formats (no archives)
#
-# compress, gzip, pack, compact, huf, squeeze, crunch, freeze, yabba, whap, etc.
+# compress, gzip, pack, compact, huf, squeeze, crunch, freeze, yabba, etc.
#
# Formats for various forms of compressed data
# Formats for "compress" proper have been moved into "compress.c",
@@ -13,14 +13,14 @@
>2 byte&0x80 >0 block compressed
>2 byte&0x1f x %d bits
-# gzip (GNU zip, not to be confused with [Info-ZIP/PKWARE] zip archiver)
+# gzip (GNU zip, not to be confused with Info-ZIP or PKWARE zip archiver)
0 string \037\213 gzip compressed data
->2 byte <8 - reserved method,
->2 byte 8 - deflate method,
->3 byte &0x01 ascii,
+>2 byte <8 \b, reserved method,
+>2 byte 8 \b, deflated,
+>3 byte &0x01 ASCII,
>3 byte &0x02 continuation,
>3 byte &0x04 extra field,
->3 byte &0x08 original file name,
+>3 byte &0x08 original filename,
>3 byte &0x10 comment,
>3 byte &0x20 encrypted,
>4 ledate x last modified: %s,
@@ -36,23 +36,22 @@
>9 byte =0x0A os: Tops/20
>9 byte =0x0B os: Win/32
-# According to gzip.h, this is the correct byte order for packed data.
-#
+# packed data, Huffman (minimum redundancy) codes on a byte-by-byte basis
0 string \037\036 packed data
->2 belong >1 %d characters originally
->2 belong =1 %d character originally
-#
-# This magic number is byte-order-independent.
-# Are there two types of old packed data? One big endian, one little endian?
+>2 belong >1 \b, %d characters originally
+>2 belong =1 \b, %d character originally
#
-#0 beshort 017437 old packed data, big endian
-#0 leshort 017437 old packed data, little endian
+# This magic number is byte-order-independent. XXX - Does that mean this
+# is big-endian, little-endian, either, or that you can't tell?
+# this short is valid for SunOS
0 short 017437 old packed data
# XXX - why *two* entries for "compacted data", one of which is
# byte-order independent, and one of which is byte-order dependent?
#
0 short 0x1fff compacted data
+# This string is valid for SunOS (BE) and a matching "short" is listed
+# in the Ultrix (LE) magic file.
0 string \377\037 compacted data
0 short 0145405 huf output
@@ -65,19 +64,18 @@
0 leshort 0x76FE crunched data (CP/M, DOS)
# Freeze
-0 string \037\237 Frozen file 2.1
-0 string \037\236 Frozen file 1.0 (or gzip 0.5)
+0 string \037\237 frozen file 2.1
+0 string \037\236 frozen file 1.0 (or gzip 0.5)
-# lzh?
-0 string \037\240 LZH compressed data
+# SCO compress -H (LZH)
+0 string \037\240 SCO compress -H (LZH) data
# European GSM 06.10 is a provisional standard for full-rate speech
# transcoding, prI-ETS 300 036, which uses RPE/LTP (residual pulse
# excitation/long term prediction) coding at 13 kbit/s.
#
-# WEAK - There's only a magic nibble (4 bits); but that nibble repeats
-# every 33 bytes. This magic is NOT suited for use, but maybe we can
-# use it someday.
+# There's only a magic nibble (4 bits); that nibble repeats every 33
+# bytes. This isn't suited for use, but maybe we can use it someday.
#
# This will cause very short GSM files to be declared as data and
# mismatches to be declared as data too!