Introduction
------------
This is a Tcl extension utilising the libmagic to provide scriptlevel access to
determine the type of a file or buffer. It either returns a descriptive text or
the mime type and optionally encoding.
License
-------
The tmag extension code is copyrighted by
Matthias Kraft <M.Kraft@gmx.com>.
It is based on Tcl's sampleextension which is copyrighted by
Scriptics Corporation, ActiveState and others.
This package is a freely available open source package. You can do virtually
anything you like with it, such as modifying it, redistributing it, and selling
it either in whole or in part.
See the file "license.terms" for complete information.
Building
--------
Building under most UNIX systems is easy, just run the configure script and then
run make. For more information about the build process, see the tcl/unix/README
file in the Tcl src dist. The following minimal example will install the
extension in the /opt/tcl directory.
$ cd tmag
$ mkdir build
$ cd build
$ ../configure --prefix=/opt/tcl --with-tcl=/opt/tcl/lib
$ make
$ make install
You will need to have the Tcl development files (headers and tclConfig script)
installed. Same thing for libmagic, magic.h must be available to the compiler.
Usage
-----
Once built and installed it can be used like this in a script:
# load extension
package require tmag
# identify a file's type with a human readable discription
set description [libmagic::filetype $file]
# identify a buffer's content returning a machine readable mimetype
set mimetype [libmagic::mimetype $buffer -isbuffer]
The prototypes of both commands are:
libmagic::filetype filename ?(-isbuffer|-follow)? ?-all? ?-raw?
libmagic::mimetype filename ?(-isbuffer|-follow)? ?-all? ?-with-encoding?
Where 'filename' is either a path to an existing file, or if '-isbuffer' is set
it is a bytearray with the content to identify. The remaining flags are:
-follow: if set and the filename points to a symlink, resolve the symlink.
Note: -follow and -isbuffer are mutual exclusive.
-all: if the content can be identified by more than one type, return all,
the first match otherwise.
-raw: do not escape non-printable characters in result text
-with-encoding: append a semi-colon and a string identifying the encoding
of the content.
--
Matthias Kraft