README for example pd external package 'hello'
Last updated for hello v0.01
The 'hello' package is an example external package intended to demonstrate one way of using GNU autotools (automake, autoconf, autoheader) to manage a Pd external distribution.
See HOWTO for a developer-oriented introduction.
Issue the following commands to the shell:
cd PACKAGE-XX.YY (or wherever you extracted the distribution) ./configure make make install
The 'configure' script supports the following options, among others:
Output a brief usage summary of the 'configure' script, including a list of supported options and influential environment variables.
Whether to enable verbose debugging messages. Default=no.
Set base Pd directory. Default PREFIX/pd
Where to look for m_pd.h
Where to install compiled externals. Default: PD_DIR/externs
Whether to build single-object externals or only multilibs (default), for packages which support both.
This section provides a brief developer-oriented description of how to use GNU autotools to manage your own Pd external package.
The directory m4/ should be copied to your top-level package directory. See ax_pd_external.m4 for details.
The file pdexternal.am should be copied to your top-level package directory See pdexternal.am for details.
The file mooPdUtils.h may be copied to your source-level directory. Currently, this only provides a PDEXT_UNUSED macro to avoid annoying gcc warnings under -W.
You must pass the ``-I m4'' flag to aclocal when you call it. For maintainer-mode rebuilding and autoreconf, you should add the following to your top-level Makefile.am:
ACLOCAL_AMFLAGS = -I m4
See the example package's autogen.sh for a useful wrapper script.
You must call the macro AX_PD_EXTERNAL from configure.ac. Before doing so (and before calling AC_PROG_CC), make sure that you cache the values of important user flags in shell variables:
##-- save user's CFLAGS,CPPFLAGS UCPPFLAGS="$CPPFLAGS" UCFLAGS="$CFLAGS" ULDFLAGS="$LDFLAGS"
##-- Pd external stuff AX_PD_EXTERNAL
See the example package's configure.ac for a complete working example.
You probably want to include $(top_srcdir)/pdexternal.am in your Makefile.am(s). This will allow you to build Pd externals as ``_PROGRAMS'' targets. In particular, pdext_PROGRAMS targets will be built as externals and installed in PDEXT_DIR (see above).
See the example package's Makefile.am for a complete working example.
To build & install the external ``hello.$(PDEXT)'', add the following to Makefile.am:
pdexterns_PROGRAMS = hello hello_SOURCES = hello.c mooPdUtils.h
To install the abstraction ``heynow.pd'', add the following to Makefile.am:
pdexterns_DATA = heynow.pd
To install the documentation patch ``hello-help.pd'', add the following to Makefile.am:
pddoc_DATA = hello-help.pd
The AX_PD_EXTERNAL macro defined in m4/ax_pd_external.m4 is intended to perform all common autoconf-level checks and substitutions necessary for building Pd external packages on various systems. Among other things, this includes:
Providing --with-FEATURE and --enable-FEATURE arguments such as --with-pd-dir (see CONFIGURATION OPTIONS, above).
Defining automake-style ``Xdir'' variables for easy definition of package externals, abstractions, and documentation.
Checking for the required header ``m_pd.h''.
Defining platform-dependent compiler and linker flags for building Pd externals, and adding these to the relevant system variables (CPPFLAGS, CFLAGS, LDFLAGS, etc.)
See the comments at the top of m4/ax_pd_external.m4 for more details on the AX_PD_EXTERNAL macro.
pdexternal.am is intended to be included in your package's Makefile.am. It redefines the automake EXEEXT to allow building Pd externals using automake's _PROGRAMS targets. Additionally, it defines the automake varibles PDEXT, SUFFIXES, EXTRA_DIST, CLEANFILES, DISTCLEANFILES, and MAINTAINERCLEANFILES.
You can use automake's EXTRA_PROGRAMS variable, together with the pdexterns_PROGRAMS automake target, the automake conditional WANT_OBJECT_EXTERNALS, and the C preprocessor macro WANT_OBJECT_EXTERNALS to allow building single-object-externals or multilibs from a single source distribution.
Makefile.am should contain something like:
##-- always build these externals pdexterns_PROGRAMS = hello
##-- potential single-object externals (as _PROGRAMS) EXTRA_PROGRAMS = goodbye
##-- build single-object externals? if WANT_OBJECT_EXTERNALS pdexterns_PROGRAMS += goodbye endif
If single-object externals were requested by the user, then the C preprocessor macro WANT_OBJECT_EXTERNALS will be defined by autoheader, to allow you to conditionally #include<> the EXTRA_PROGRAMS sources in your top-level multilib source file if desired. In the above example, hello.c might contain:
#ifdef HAVE_CONFIG_H # include "config.h" #endif
#ifndef WANT_OBJECT_EXTERNALS /*-- Multilib build: include source for the goodbye external --*/ # include "goodbye.c" #endif
/*... local definitions etc. go here ...*/
void hello_setup(void)
{
#ifndef WANT_OBJECT_EXTERNALS
goodbye_setup();
#endif
/*... local setup code goes here ...*/ }
PD by Miller Puckette and others.
Bryan Jurish <moocow@ling.uni-potsdam.de>