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# status

experimental


# intro

q.b provides functionality similar to static linking:  making a
program self-contained.

q.b is a stand-alone 9p2000 server that can serve an embedded file
tree (including data of files) and run a program from that tree.
it only uses limbo modules built into the inferno dis vm.

q.b includes a file called data.b.  this file must hold an assignment
to the array of byte "data".  this data represents the file tree,
it can be generated with qmk.  data.b can also be left empty, and
q.dis run with a file containing the file tree as a parameter.

qmk reads a list of files to include from stdin, and writes a file
tree usable by q.dis to stdout.  with option -x, the output is
suitable to be a data.b.  each line of input must contain one or
two fields, tab-separated.  the first field is the file/dir name
in q's file system.  if the second field is present, it points to
the file in the local file system to use for its (meta)data.  this
is similar to conf(10)'s root section.  qmk also needs at least one
parameter.  the parameters are the command line that will be executed
by q.b.  the first parameter must be the dis file to load and run.

q requires that directories are specified explicitly too, i.e. the
file "a/b" must be preceded by the file (directory) "a".  the root
directory should not be specified explicitly.

qgen is a shell script that generates a list of files and directories
to include when given a dis file.  it uses disdep to generate
dependencies.  it does not otherwise know about files and directories
used by the program, so those will still have to be specified
separately.

the following example (must be run from within inferno) creates a
version of ls(1) that does not require external libraries.

	cd appl/cmd
	qgen /dis/ls.dis | qmk -x /dis/ls.dis -l >data.b
	cp q.b qlsl.b
	limbo -gw qlsl.b
	bind /tmp /dis  # to make sure we're not cheating
	./qlsl.dis

warnings:
you may have to increase the allowed stack usage for the limbo
compiler, compiling a q.b with a huge data.b consumes a lot of
stack.

as long as the program(s) started by q.b live and keep their
namespace, q's processes stay alive and must not be killed.


# install

use of q.b will require some changes to your build environment.
qmk can be build as follows:

make sure $ROOT is set.  now "mk install" to compile and install the
files.

when building from within inferno, insert SYSHOST=Inferno and ROOT=
in the mk invocations to override the values in the mkconfig.


# latest version

the latest version can be found at:

    http://www.ueber.net/code/r/q


# licence & author

all files are in the public domain.  this code has been written by
mechiel lukkien, reachable at [email protected].