GNU Autoconf 2.12 for EMX

Table of contents

• Table of contents
• Introduction
• How it works
• Requirements for running
• A simple instal from the binaries
• A not so simple install from the sources
• Using autoconf
• Important notes
• Bug reports
• Greettings
• Getting it

Introduction

What I've found that makes porting more difficult is sometimes building all those makefiles and configuration headers. Under Linux and most *nix like O.S. you would run a configure script that guesses most of your system peculiarities (Name of the C/C++ compiler, which headers and libraries are present, whether a function is broken...). But OS/2 is not Unix --nor even similar--- and there are enough differences to break up those configuration scripts, even if you already have a sh-like shell.

OK, it was the state of the question until now. This port of Autoconf introduces a set of scripts and macro files able to build scripts that work well under OS/2 with EMX using all those wonderful ports of GNU utilities.

Requirements for running Autoconf

• GNU file, text and shell utilitities
• GNU m4 macro processor
• Korn Shell 5.2.13 or newer --watch the number!!-- or Ash --available at this site--. If you use Ash, make sure you have the latest release (>= ash-0.2-4).
• Most of the times you'll need AWK. Get a standard one (Maybe GNU's)
• GNU make. Make sure it is <= 3.74. You can also use XfreeOS/2 x11make.exe which is nothing but GNU Make 3.71, but never use make.cmd, the wrapper for x11make.exe.

How it works

• When looking for executable programs, check not only for program files, but also for program.exe and program.cmd
• Avoid looking for executable files in OS/2 & Window's directories (the reason for doing this is that the GNU install utility has the same name as the install program from OS/2 & Win).
• When splitting PATH use semicolon ";" as a separator, not a double colon ":".
• Instead of manipulating PATH, save its value in FPATH, translate "\" into "/" and work with this last one.
• Add some important defaults at the begining of every script, such as the name of the compiler and other important options needed to compile programs with EMX.
• Add rules for undestanding unit names.

A simple install from the binaries

• Make a directory for Autoconf. Let's say it is c:\apps\autoconf
• Unpack the binary distribution packet (autoconf*emxbin.zip) there.
• Add that directory to PATH or either move the script files autoconf, autoreconf, autoheader, autoscan, autoupdate and ifnames to some other directory which *is* listed in PATH.
• Define an environment variable named AC_MACRODIR that points to the place where you unpacked aconf*b.zip. For instance, if it was c:\apps\autoconf, add the following line to your config.sys:
  SET AC_MACRODIR=c:/apps/autoconf Beware with slashes: you must use `/', not `\'.
• You're free to move the documentation (*.info* files) to any place which is listed in INFOPATH. (Note: *.info* files may not be in the package if this is a test release)
• If you ever happen to need AWK to run Autoconf, make sure you have an executable named `awk.exe' or either set the AWK environment variable: for instance, in my system it would be
  set AWK=e:/usr/bin/gawk.exe

A not so simple install from the sources

Requisites

• GNU make up to 3.74 (The newest make is not case sensitive and may cause conflicts with some makefiles). If you have the XFreeOS/2 Toolkit for Programmers, make sure you always invoke make.exe or x11make.exe and not the make.cmd script that comes with XFreeOS/2 (At home, I renamed make.exe as gmake.exe and use this last one).

Steps

• Move into autoconf's directory.
• Start an system shell and type "build --clean". This should remove any file from configure config.cache config.status config.log. (Note: autoconf's options are case sensitive, that is, use always lowercase for them) Alternatively, you can remove those files by hand.
• Now simply type build and you'll get a configure script about 32K's long.
• Create a unix-like directory structure. My system has the following one
  e:/usr
  e:/usr/bin
  e:/usr/info
  ...
  e:/usr/local
  e:/usr/local/bin
  e:/usr/local/info
  ...

  and /usr/bin and /usr/local/bin are in the PATH. When installing, Autoconf chooses the root directory you tell it (in my system it could be either e:/usr or e:/usr/local), builds several directories inside it uses them to stores scripts, info and macro files. Suppose the `root' is e:/usr/local then

  • e:/usr/local/bin should be in PATH
  • e:/usr/local/bin is where scripts will be stored
  • e:/usr/local/info is where the documentation will be stored
  • e:/usr/local/share/autoconf is where the macro files will be
• At the command prompt type something like "sh configure --prefix=your_root_directory" where sh is the name of your unix-like shell. This will tipically find m4, awk --and perl.exe in case you have it-- and create customized makefiles for autoconf.

  For example, in my system (described above, I would use) sh configure --prefix=e:/usr/local

• Invoke GNU make. You can either use make.exe, or even call x11make.exe if you have the XFreeOS/2 programmer's toolkit. But never use a simple make as the XFreeOS/2 make.cmd could pop up and mess the deal. This builds the customized scripts autoconf, autoheader, autoreconf, autoupdate, and ifnames.
• If everything went right, type "make.exe install", and you'll have the scripts, the macro files and the info files installed.
• IMPORTANT: Save a copy of config.sub, config.guess, install-sh and mkinstalldirs as you might need them to port your program.

Using autoconf

• Move into the directory which has the code you want to port.
• The configure file must be already there: rename it to configure.bak.
• Copy Autoconf's config.sub, config.guess & install-sh, there, before it's too late :)
• You should also replace mkinstalldirs with the one that comes in Autoconf for EMX, as this last one understands drive unit names.
• Type sh -c "autoconf --clean" to remove configure's auxiliary files: this should be done every time configure is rebuilt or after anything in your system changed (new programs installed, new PATH, etc) so that configure cares for those changes.
• Type sh -c autoconf to get a brand new configure.
• If you know your program is going to need some special flags, such as -Zmt, -D__ST_MT_ERRNO__, etc, then edit the lines in configure for CCFLAGS (C compiling flags), CXXFLAGS (C++ compiling flags), LDFLAGS (Flags for linking).

  Alternatively, you can export environment variables prior to using configure overriding the checks it could do. For instance, a

  	set MAKE=gmake.exe
  	set CFLAGS=-O -Zmt
  	set CXXFLAGS=-O -Zmt
  	set LDFLAGS=-Zexe -Zmtd -Zsysv-signals
  

  would choose the appropiate name for the MAKE utility and the appropiate flags for compiling an XFreeOS/2 program.
• Run sh ./configure with any other options you wish. Usually

  	sh ./configure --help
  

  would inform you about the available options (programs to build, extensions, checks to avoid or include, etc), whereas

  	sh ./configure --prefix=d:/usr
  

  would configure using default settings and defining the root directory to be d:/usr.
• Watch the output: if the script can't find a program, library or file you DO have; or if some strange error comes out, please e-mail me but don't abuse the author (See Bug reports)
• Check all the files that have been updated (configure shows their names). They're usually makefiles and a config.h. If you see a path messed (i.e. /usr/../c:/usr/bin/sh.exe) and you cannot figure out why configure failed, tell me. (See Bug reports)
• Now do the real port: check the code and fix it. Here I cannot help you ;)

• The use of fork and exec is not recommended if you want your program to run under DOS. And even under OS/2 it wastes a lot of resources and slows programs a lot.
• Unix programs don't understand disk units names, such as 'C:'. This can be a real drawback in many ports.
• Unix text files use simple newline characters, while DOS and OS/2 use newline plus carriage return. This implies that files have to be opened with special flags (O_BINARY, "b", O_TEXT, "t") that distinguish between text and binary files.

News in this package

• We move up to version 2.12
• Checks for X are fixed --now they understand X11ROOT--.
• Flag `-g' removed and `-Zcrtdll' added to reduce the size of programs.
• Added some patches that simplify the load on the shell and let you use this Autoconf with NCurses-4.1 (Contribution of T.E.Dickey)
• Added flags for building bug reports.

Important notes

• Hey, this is work in progress, don't expect miracles!!!
• All usual disclaimers apply
• Read the GNU license that comes with the packages
• Read the file ChangesLog.os2 for important changes, features and maybe bugs.

Bug reports

When reporting bugs, follow these steps:

• Make sure you have the required utilities configured and properly installed in your system.
• Use sh -c "autoconf --debug" to rebuild the configure script that doesn't seem to work.
• Run the rebuilt file with something like

  	sh ./configure 2>&1 error.log
  

  and e-mail me the error.log, config.log, config.status and config.cache files. You can pack them with any well-known archiver (ZIP, tar+gzip, LZH, ZOO).
• Be patient :)

Greettings

Getting it

• Go up: Main index
• Maintainer: Juan Jose Garcia Ripoll <worm@arrakis.es>