Provided by: critcl_3.3.1+dfsg-1_amd64 bug

NAME

       critcl_devguide - Guide To The CriTcl Internals

DESCRIPTION

       Be  welcome  to the C Runtime In Tcl (short: CriTcl), a system for embedding and using C code from within
       Tcl [http://core.tcl-lang.org/tcl] scripts.

AUDIENCE

       This document is a guide for developers working on CriTcl, i.e. maintainers fixing  bugs,  extending  the
       package's functionality, etc.

       Please read

       [1]    CriTcl - License,

       [2]    CriTcl - How To Get The Sources, and

       [3]    CriTcl - The Installer's Guide

       first, if that was not done already.

       Here  we assume that the sources are already available in a directory of the readers choice, and that the
       reader not only know how to build and install them, but also has all the necessary requisites to actually
       do so. The guide to the sources in particular also explains which source code management system is  used,
       where to find it, how to set it up, etc.

PLAYING WITH CRITCL

       Note  that the sources of CriTcl, should the reader have gotten them, also contain several examples show-
       casing various aspects of the system. These demonstration packages can all be found in the  sub-directory
       "examples/" of the sources.

       Lots of smaller examples can be found in the document Using CriTcl, an introduction to CriTcl by way of a
       of  examples.  These  focus  more on specific critcl commands than the overall picture shown by the large
       examples mentioned in the previous paragraph.

DEVELOPING FOR CRITCL

   ARCHITECTURE & CONCEPTS
       The system consists of two main layers, as seen in the figure below,  plus  a  support  layer  containing
       general packages the system uses during operation.

       +----------------+
       |Applications    |
       | critcl         |
       | critcl::app    |
       +----------------+

       +----------------+
       |Core Packages   |
       | critcl         |
       | critcl::util   |
       +----------------+

       +----------------+
       |Support Packages|
       | stubs::*       |
       | md5, platform  |
       |  ...           |
       +----------------+

       [1]    At the top we have an application built on top of the core packages, providing command line access
              to the second and third usage modes, i.e. Generate Package and Generate TEA Package.

              critcl

              critcl::app

       [2]    Below  that  is the core package providing the essential functionality of the system, plus various
              utility packages which make common tasks more convenient.

              critcl

              critcl::util

       [3]    Lastly a layer of supporting packages, mostly external to critcl.

              md5    For this pure-Tcl package to be fast users should get one of several  possible  accelerator
                     packages:

                     [1]    tcllibc

                     [2]    Trf

                     [3]    md5c

              cmdline

              platform

              stubs::container

              stubs::reader

              stubs::writer

              stubs::gen

              stubs::gen::init

              stubs::gen::header

              stubs::gen::decl

              stubs::gen::macro

              stubs::gen::slot

              stubs::gen::lib

   REQUIREMENTS
       To develop for critcl the following packages and applications must be available in the environment. These
       are all used by the build.tcl helper application.

       dtplite
              A  Tcl  application  provided  by  Tcllib, for the validation and conversion of doctools-formatted
              text.

       dia    A Tcl application provided by Tklib,  for  the  validation  and  conversion  of  diagram-formatted
              figures into raster images.

              Do  not  confuse  this with the Gnome dia application, which is a graphical editor for figures and
              diagrams, and completely unrelated.

       fileutil
              A Tcl package provided by Tcllib, providing file system utilities.

       vfs::mk4, vfs
              Tcl packages written in C providing access to Tcl's VFS facilities, required for the generation of
              critcl starkits and starpacks.

   DIRECTORY STRUCTURE
       Helpers

              "build.tcl"
                     This helper application provides various operations needed by a developer for critcl,  like
                     regenerating the documentation, the figures, building and installing critcl, etc.

                     Running the command like

                       ./build.tcl help

                     will provide more details about the available operations and their arguments.

       Documentation

              "doc/" This directory contains the documentation sources, for both the text, and the figures.  The
                     texts are written in doctools format, whereas the figures are written for tklib's dia(gram)
                     package and application.

              "embedded/"
                     This  directory  contains the documentation converted to regular manpages (nroff) and HTML.
                     It is called embedded because these files, while derived, are part of the  git  repository,
                     i.e.  embedded  into  it.  This enables us to place these files where they are visible when
                     serving the prject's web interface.

       Testsuite

              "test/all.tcl"

              "test/testutilities.tcl"

              "test/*.test"
                     These files are a standard testsuite based on Tcl's tcltest package, with some utility code
                     snarfed from Tcllib.

                     This currently tests only some of the stubs::* packages.

              "test/*.tcl"
                     These files (except for "all.tcl" and "testutilities.tcl")  are  example  files  (Tcl  with
                     embedded C) which can be run through critcl for testing.

                     TODO for a maintainers: These should be converted into a proper test suite.

       Package Code, General structure

       Package Code, Per Package

              critcl

                     "lib/critcl/critcl.tcl"
                            The Tcl code implementing the package.

                     "lib/critcl/Config"
                            The configuration file for the standard targets and their settings.

                     "lib/critcl/critcl_c/"
                            Various  C  code  snippets  used  by  the package.  This directory also contains the
                            copies of the Tcl header files used to compile the assembled C code, for  the  major
                            brnaches of Tcl, i.e. 8.4, 8.5, and 8.6.

              critcl::util

                     "lib/critcl-util/util.tcl"
                            The Tcl code implementing the package.

              critcl::app

                     "lib/app-critcl/critcl.tcl"
                            The Tcl code implementing the package.

              critcl::iassoc

                     "lib/critcl-iassoc/iassoc.tcl"
                            The Tcl code implementing the package.

                     "lib/critcl-iassoc/iassoc.h"
                            C code template used by the package.

              critcl::class

                     "lib/critcl-class/class.tcl"
                            The Tcl code implementing the package.

                     "lib/critcl-class/class.h"
                            C code template used by the package.

              stubs::*

                     "lib/stubs/*"
                            A  set  of  non-public  (still)  packages which provide read and write access to and
                            represent Tcl stubs tables. These were created by taking the  "genStubs.tcl"  helper
                            application coming with the Tcl core sources apart along its internal logical lines.

              critclf

                     "lib/critclf/"
                            Arjen  Markus'  work  on  a  critcl/Fortran.  The  code is outdated and has not been
                            adapted to the changes in critcl version 3 yet.

              md5

              md5c

              platform
                     These are all external packages whose code has been inlined in the  repository  for  easier
                     development  (less  dependencies  to  pull),  and  quicker  deployment  from the repository
                     (generation of starkit and -pack).

                     TODO for maintainers: These should all be checked against  their  origin  for  updates  and
                     changes since they were inlined.

AUTHORS

       Jean Claude Wippler, Steve Landers, Andreas Kupries

BUGS, IDEAS, FEEDBACK

       This  document,  and  the package it describes, will undoubtedly contain bugs and other problems.  Please
       report them at https://github.com/andreas-kupries/critcl/issues.  Ideas for enhancements you may have for
       either package, application, and/or the documentation are also very welcome and  should  be  reported  at
       https://github.com/andreas-kupries/critcl/issues as well.

KEYWORDS

       C  code,  Embedded C Code, calling C code from Tcl, code generator, compile & run, compiler, dynamic code
       generation, dynamic compilation, generate package, linker, on demand compilation, on-the-fly compilation

CATEGORY

       Glueing/Embedded C code

COPYRIGHT

       Copyright (c) Jean-Claude Wippler
       Copyright (c) Steve Landers
       Copyright (c) 2011-2024 Andreas Kupries

doc                                                   3.3.1                                critcl_devguide(3tcl)