diff options
Diffstat (limited to 'contrib/file/doc/magic.man')
-rw-r--r-- | contrib/file/doc/magic.man | 30 |
1 files changed, 18 insertions, 12 deletions
diff --git a/contrib/file/doc/magic.man b/contrib/file/doc/magic.man index bc37404..4c69bca 100644 --- a/contrib/file/doc/magic.man +++ b/contrib/file/doc/magic.man @@ -1,5 +1,5 @@ -.\" $File: magic.man,v 1.88 2016/07/27 09:42:49 rrt Exp $ -.Dd July 20, 2016 +.\" $File: magic.man,v 1.91 2017/02/12 15:30:08 christos Exp $ +.Dd February 12, 2017 .Dt MAGIC __FSECTION__ .Os .\" install as magic.4 on USG, magic.5 on V7, Berkeley and Linux systems. @@ -7,7 +7,7 @@ .Nm magic .Nd file command's magic pattern file .Sh DESCRIPTION -This manual page documents the format of the magic file as +This manual page documents the format of magic files as used by the .Xr file __CSECTION__ command, version __VERSION__. @@ -17,13 +17,19 @@ command identifies the type of a file using, among other tests, a test for whether the file contains certain .Dq "magic patterns" . -The file -.Pa __MAGIC__ -specifies what patterns are to be tested for, what message or +The database of these +.Dq "magic patterns" +is usually located in a binary file in +.Pa __MAGIC__.mgc +or a directory of source text magic pattern fragment files in +.Pa __MAGIC__ . +The database specifies what patterns are to be tested for, what message or MIME type to print if a particular pattern is found, and additional information to extract from the file. .Pp -Each line of the file specifies a test to be performed. +The format of the source fragment files that are used to build this database +is as follows: +Each line of a fragment file specifies a test to be performed. A test compares the data starting at a particular offset in the file with a byte value, a string or a numeric value. If the test succeeds, a message is printed. @@ -98,13 +104,13 @@ The following modifiers are supported: .It B A byte length (default). .It H -A 2 byte big endian length. +A 4 byte big endian length. .It h -A 2 byte big little length. +A 2 byte big endian length. .It L -A 4 byte big endian length. +A 4 byte little endian length. .It l -A 4 byte big little length. +A 2 byte little endian length. .It J The length includes itself in its count. .El @@ -651,7 +657,7 @@ start of the main indirect offset. \*[Gt]\*[Gt]\*[Gt]\*[Gt](\*[Am]0xe.l+(-4)) string PK\e3\e4 \eb, ZIP self-extracting archive .Ed .Pp -If you have a list of known avalues at a particular continuation level, +If you have a list of known values at a particular continuation level, and you want to provide a switch-like default case: .Bd -literal -offset indent # clear that continuation level match |