README.MinGW ============ Contributed by Keith Marshall (keith.d.marshall@ntlworld.com) INTRODUCTION ------------ This file provides recommendations for building a Win32 implementation of GNU Groff, using the MinGW port of GCC for Microsoft (TM) Windows-32 platforms. It is intended to supplement the standard installation instructions (see file INSTALL); it does not replace them. You require both the MinGW implementation of GCC and its supporting MSYS toolkit, which provides a Win-32 implementation of the GNU bash shell, and a few other essential utilities; these may be obtained from http://sourceforge.net/projects/mingw by following the appropriate download links, where they are available as self-extracting executable installation packages. If installing both from scratch, it is recommended that MinGW is installed first, as the MSYS installer can then automatically set up the proper environment for running MinGW. Additionally, if you wish to compile groff with support for its HTML output capability, some additional tools are required as decribed in the section PREREQUISITES FOR HTML OUTPUT later in this file. BUILDING GROFF WITH MINGW ------------------------- Assuming that you have obtained the appropriate groff distribution, and that you are already running an MSYS shell, then the configuration, compilation, and installation of groff, using MinGW, is performed in much the same way as it is described in the INSTALL file, which is provided with the groff distribution. The installation steps are summarised below: 1. Change working directory to any suitable location where you may unpack the groff distribution; you must be authorized for write access. Approximately 30MB of free disk space are needed. 2. Unpack the groff distribution: tar xzf /groff-.tar.gz This creates a new sub-directory, groff-, containing an image of the groff source tree. You should now change directory, to make this ./groff- your working directory. 3. If you are intending to build groff with support for HTML output, then you must now ensure that the prerequisites described in the later section PREREQUISITES FOR HTML OUTPUT are satisfied, before proceeding to build groff; in particular, please ensure that all required support programs are installed in the current PATH. 4. You are now ready to configure, build, and install groff. This is accomplished using the conventional procedure, as described in the file INSTALL, i.e. ./configure --prefix= ... make make install Please observe the syntax for the configure command, indicated above; the default value for --prefix is not suitable for use with MinGW, so the --prefix= option must be specified, where is the chosen MS-Windows directory in which the groff application files are to be installed (see the later section entitled CHOOSING AN INSTALLATION PATH). Any other desired configuration options may also be specified, as described in the standard groff installation instructions. 5. After completing the above, groff should be successfully installed; the build directory is no longer required; it may be simply deleted in its entirety. Alternatively, you may choose to keep it, but to remove all files which can be reproduced later, by repeating the configure, make and make install steps; this is readily accomplished by the command make distclean This completes the installation of groff; please read the final sections of this file, GROFF RUNTIME ENVIRONMENT and CAVEATS AND BUGS, for advice on setting up the runtime environment, and avoiding known runtime problems, before running groff. CHOOSING AN INSTALLATION PATH ----------------------------- It may be noted that the above instructions indicate that the ./configure command must be invoked with an argument specifying a preference for --prefix=, whereas the standard groff installation instructions indicate that this may be omitted, in which case it defaults to --prefix=/usr/local. In the case of building with MinGW, the default behaviour of configure is not appropriate for the following reasons. o The MSYS environment creates a virtual UNIX-like file system, with its root mapped to the actual MS-Windows directory where MSYS itself is installed; /usr is also mapped to this MSYS installation directory. o All of the MSYS tools, and the MinGW implementation of GCC, refer to files via this virtual file system representation; thus, if the --prefix= is not specified when groff is configured, `make install' causes groff to be installed in /local. o groff needs to know its own installation path, so that it can locate its own installed components. This information is compiled in, using the exact form specified with the --prefix= option to configure. o Knowledge of the MSYS virtual file system is not imparted to groff; it expects the compiled-in path to its components to be a fully qualified MS-Windows path name (although UNIX-style slashes are permitted, and preferred to the MS-Windows style backslashes, to demarcate the directory hierarchy). Thus, when configuring groff, if --prefix= is not correctly specified, then the installed groff application looks for its components in /usr/local, and most likely doesn't find them, because they are actually installed in /local. It is actually convenient, but by no means a requirement, to have groff installed in the /usr/local directory of the MSYS virtual file system; this makes it easy to invoke groff from the MSYS shell, since the virtual /usr/local/bin is normally added automatically to the PATH (the default PATH, as set in MSYS's /etc/profile), when MSYS is started. In order to install groff into MSYS's /usr/local directory, it is necessary to specify the fully qualified absolute MS-Windows path to this directory, when configuring groff, i.e. ./configure --prefix=/local ... For example, on a system where MSYS is installed in the MS-Windows directory D:\MSYS\1.0, the MSYS virtual path /usr/local resolves to the absolute MS-Windows native path D:\MSYS\1.0\local (the /usr component of the MSYS virtual path does not appear in the resolved absolute native path name since MSYS maps this directly to the root of the MSYS virtual file system). Thus, the --prefix option should be specified to configure as ./configure --prefix=D:/MSYS/1.0/local ... Note that the backslash characters, which appear in the native MS-Windows form of the path name, are replaced by UNIX-style slashes in the argument to configure; this is the preferred syntax. Also note that the MS-Windows device designator (D: in this instance) is prepended to the specified path, in the normal MS-Windows format, and that, since upper and lower case distinctions are ignored in MS-Windows path names, any combination of upper and lower case is acceptable. PREREQUISITES FOR HTML OUTPUT ----------------------------- If you intend to use groff for production of HTML output, then there are a few dependencies which must be satisfied. Ideally, these should be resolved before attempting to configure and build groff, since the configuration script does check them. In order to produce HTML output, you first require a working implementation of Ghostscript; either the AFPL Ghostscript or the GNU Ghostscript implementation for MS-Windows should be suitable, depending on your licensing preference. It is highly recommended to use version 8.11 or higher due to bugs in older versions. These may be obtained, in the form of self-installing binary packages, by following the download links for the chosen licensing option, from http://sourceforge.net/projects/ghostscript. Please note that these packages install the Ghostscript interpreter required by groff in the ./bin subdirectory of the Ghostscript installation directory, with the name gswin32c.exe. However, groff expects this interpreter to be located in the system PATH, with the name gs.exe. Thus, to ensure that groff can correctly locate the Ghostscript interpreter, it is recommended that the file gswin32c.exe should be copied from the Ghostscript installation directory to the MSYS /usr/local/bin directory, where it should be renamed to gs.exe. In addition to a working Ghostscript interpreter, you also require several image manipulation utilities, all of which may be scavenged from various packages available from http://sourceforge.net/projects/gnuwin32, and which should be installed in the MSYS /usr/local/bin directory, or any other suitable directory which is specified in the PATH. These additional prerequisites are 1. from the netpbm--bin.zip package: netpbm.dll pnmcrop.exe pnmcut.exe pnmtopng.exe pnmtops.exe 2. from the libpng--bin.zip package: libpng.dll 3. from the zlib--bin.zip package: zlib-1.dll, which must be renamed to zlib.dll 4. from the psutils--bin.zip package: psselect.exe Note that it is not necessary to install the above four packages in their entirety; of course, you may do so if you wish. GROFF RUNTIME ENVIRONMENT ------------------------- The runtime environment, provided to groff by MSYS, is essentially the same as would be provided under a UNIX or GNU/Linux operating system; thus, any environment variables which may be used to customize the groff runtime environment have similar effects under MSYS, as they would in UNIX or GNU/Linux, with the exception that any variable specifying a path should adopt the same syntax as a native MS-Windows PATH specification. There is, however, one known problem which is associated with the implementation of the MS-Windows file system, and the manner in which the Microsoft runtime library (which is used by the MinGW implementation of GCC) generates names for temporary files. This known problem arises when groff is invoked with a current working directory which refers to a network share, for which the user does not have write access in the root directory, and there is no environment variable set to define a writeable location for creating temporary files. When these conditions arise, groff fails with a `permission denied' error, as soon as it tries to create any temporary file. To specify the location for creating temporary files, the standard UNIX or GNU/Linux implementation of groff provides the GROFF_TMPDIR or TMPDIR environment variables, whereas MS-Windows applications generally use TMP or TEMP; furthermore, the MS-Windows implementations of Ghostscript apparently support the use of only TEMP or TMPDIR. To avoid problems with creation of temporary files, it is recommended that you ensure that both TMP and TEMP are defined, with identical values, to point to a suitable location for creating temporary files; many MS-Windows boxes have them set already, and groff has been adapted to honour them, when built in accordance with the preceding instructions, using MinGW. CAVEATS AND BUGS ---------------- There are two known issues, observed when running groff in the MinGW/MSYS environment, which would not affect groff in its native UNIX environment: o Running groff with the working directory set to a subdirectory of a network share, where the user does not have write permission in the root directory of the share, causes groff to fail with a `permission denied' exception, if the TMP environment variable is not appropriately defined; it may also be necessary to define the TEMP environment variable, to avoid a similar failure mode, when using the -Thtml output mode of groff. This problem is more fully discussed in the preceding section, GROFF RUNTIME ENVIRONMENT. o When running groff (or nroff) to process standard input, where the standard input stream is obtained directly from the RXVT console provided with MSYS, groff cannot detect the end-of-file condition for the standard input stream, and hangs. This appears to be caused by a fault in the MSYS implementation of RXVT; it may be worked around by either starting MSYS without RXVT (see the comments in the MSYS.BAT startup script); in this case standard input is terminated by typing followed by , on a new input line. Alternatively, if you prefer to use MSYS with RXVT, you can enter the interactive groff command in the form cat | groff ... in which case terminates the standard input stream, in just the same way it does on a UNIX system; the cat executable provided with MSYS does seem to trap the end-of-file condition, and properly signals groff that the input stream has terminated.