Hey,

thanks to everyone who responded to my posts both here and in the mailing list. Since then, I've figured out how to compile externals written in C using Microsoft Visual C++ 2005. There's more to document, however, such as how to compile externals using some of the other Windows compilers (Borland, djgpp, etc.), and also how to compile externals written in C++ in Windows. But one thing at a time.

one little thing to note... steps 4 and 7 may seem a little roundabout, but they account for the fact that MSVC sometimes has trouble with spaces in directory names (eg. C://Program Files/). If anyone knows how to override this behavior, post a reply, and I'll try to simplify the steps accordingly.

Updated June 29, 2007:
use [b]C://Progra~1/[/b] instead of [b]C://Program Files/[/b],
use [b]C://Docume~1/[/b] instead of [b]C://Documents and Settings/[/b], etc.

So, without further ado...

How to compile a pd external written in C using Microsoft Visual C++ 2005:

Compared to Windows, linux offers a much more user-friendly environment for compiling pd externals. However, with a little patience, a usable environment can be set up in Windows, and the good news is that everything you need is available for free. There are several reputable Windows-compatible C/C++ compilers out there, but here I'll discuss compiling externals with Microsoft Visual C++ 2005 (MSVC for short).

1. Download and Install Microsoft Visual C++ 2005 Express Edition.
a. Click the link above, then click Go! in the Visual C++ box.
b. Run vcsetup.exe to install the program
(the setup wizard should guide you through the process).

2. Download [url=http://download.microsoft.com/download/7/7/3/7737290f-98e8-45bf-9075-85cc6ae34bf1/VS80sp1-KB9267
]Visual C++ 2005 Express Service Pack 1.
a. Click the link above to download the Service Pack.
b. Run VS80sp1-KB926748-X86-INTL.exe to install the program.

3. Create a new project:
a. Open Visual C++.
b. Open the New Project window (Ctrl+Shift+N).
c. In the Project Types pane, select Visual C++.
d. In the Templates pane, select emptyproj.
e. Enter object name (helloworld).
f. Leave Create directory for solution unchecked, and click OK.

4. Import the pd header file:
a. Get m_pd.h here, or, using pd-vanilla (not pd-extended):
1. Open Windows Explorer or My Computer.
2. Navigate to the pd/src/ directory on your system.
3. Open m_pd.h in a text editor (file type is: C/C++ header).
b. Select all (Ctrl+A).
c. Copy selection to the clipboard (Ctrl+C).
d. Back in Visual C++, open the New File window (Ctrl+N).
e. In the Categories pane, select General.
f. In the Templates pane, select Text File, and click Open.
g. Copy the contents of m_pd.h into the editor window (Ctrl+V).
h. Open the Save File As Window (Ctrl+S).
i. Save as m_pd.h.
j. From the File Menu, select Move m_pd.h into; select helloworld.

5. Write the source code for the external in C.
a. Open the New File window (Ctrl+N).
b. In the Categories pane, select General.
c. In the Templates pane, select Text File, and click Open.
d. Write your source code in the editor window.

The following example is taken from the tutorial by Johannes M. Zmoelnig.

#include "m_pd.h"

static t_class *helloworld_class;

typedef struct _helloworld {
  t_object  x_obj;
} t_helloworld;

void helloworld_bang(t_helloworld *x)
{
  post("Hello world !!");
}

void *helloworld_new(void)
{
  t_helloworld *x = (t_helloworld *)pd_new(helloworld_class);

  return (void *)x;
}

void helloworld_setup(void) {
  helloworld_class = class_new(gensym("helloworld"),
        (t_newmethod)helloworld_new,
        0, sizeof(t_helloworld),
        CLASS_DEFAULT, 0);
  class_addbang(helloworld_class, helloworld_bang);
}

6. Save and import the source code into the project:
a. Open the Save File As Window (Ctrl+S).
b. Save as helloworld.c.
c. From the File Menu, select Move helloworld.c into; select helloworld.

7. Access the pd library file:
a. Open Windows Explorer or My Computer.
b. Navigate to the pd/bin/ directory on your system.
c. Right-click on pd.lib (file type is: Object File Library) and select Copy.
d. Navigate to the C://TEMP/ directory on your system.
e. Paste the copy of pd.lib in the C://TEMP/ directory (right-click or Ctrl-V).

8. Set configuration properties:
a. Set configuration type to .dll:
1. Back in Visual C++, open the helloworld Property Pages window (Alt+F7).
2. In the left pane, select Configuration Properties >> General.
3. In the right pane, under Project Defaults, click on
Configuration Type, and select Dynamic Library (.dll)
(using the arrow on the right).

b. Add MSW to preprocessor definitions:
1. In the left pane, select
Configuration Properties >> C/C++ >> Preprocessor.
2. In the right pane, type MSW in the Preprocessor Definitions field.

c. Tell compiler which language to use:
1. In the left pane, select
Configuration Properties >> C/C++ >> Advanced.
2. In the right pane, select Compile As.
3. Select Compile as C Code (/TC) by clicking the arrow on the right.

d. Tell linker where to find pd.lib:
1. In the left pane, select Configuration Properties >> Linker >> Input.
2. In the right pane, select Additional Dependencies and enter
C://TEMP/pd.lib.

e. Tell linker to export the setup function:
1. In the left pane, select
Configuration Properties >> Linker >> Command Line.
2. In the right pane, type
/export:helloworld_setup in the Additional options field.
3. Click OK.

9. Compile and link:
a. Use the Build Solution command (F7).

10. Copy the new helloworld.dll file into pd.
a. Open Windows Explorer or My Computer.
b. Navigate to the
My Documents/Visual Studio 2005/Projects/helloworld/Debug/
directory on your system.
c. Right-click on helloworld.dll (file type is: Application Extension)
and select Copy.
d. Navigate to the pd/extra directory on your system.
e. Paste the copy of helloworld.dll in the pd/extra directory
(right-click or Ctrl-V).

11. Test the external in pd.
a. the external should now be a useable object in pd.
b. open a new pd patch and try to create a helloworld object.
c. add a bang to the left inlet and test it out.
d. if the main pd console window displays "Hello world !!",
the external has succeeded.

Hope this helps!
-- middlepedal

This has been answered on pd-list today
Hopefully this is helpful to others. I never go near Windows myself,
but anyway, post copied verbatim for the benefit of all...

> Iohannes Zmoelnig wrote:

> have you tried any online resources: e.g.
> http://puredata.info/docs/developer lists at least 2 pages that only
> deal with compiling on windows
> (http://puredata.info/docs/developer/mingw which basically deals with
> compiling pd itself on windows; but once you are there, it is simple;
> http://nul.jp/2002/pd_bc deals with compiling externals with the
> borland-compiler).

> i can give you a step-by-step guide for compiling zexy though (but mind
> that this is how i _remember_ it; i will not go and search for a windows
> machine with VC installed just to verify each step).

> - purchase M$ VC6 (elitarism on my side...:-)) and install it
> - get pd
> - download zexy (sources!) for free (e.g.
> ftp://ftp.iem.at/pub/pd/Externals/ZEXY/)
> - extract zexy to you favourite folder
> - double-click on the zexy.dsp (or was it zexy.dsw??) in the zexy/src/
> folder; this should open VC
> - to to the Project->Properties (or however this is called in your
> locale) and change the settings to match your setup (mainly these are
> the paths to find pd's headers and libraries; you should basically go
> through every item in the settings for the "release" and/or "debug"
> builds; the most important stuff is in "compiler->preprocessor",
> "compiler->path" and "linker->path"
> - when you are finished, return to the main project window
> - hit "F7" to start the build.
> - if you encounter any errors, either the settings are not yet correct
> (return to item-6) or the project is a bit out-of-date; the latter
> basically means, that the c-files to be included have not been updated;
> to fix this, just delete all the c-files from the project file browser
> (here this used to be un the left-side of the project-window), then
> right click on the folder in the project file browser that used to
> contain these files and select "add"; in the openpanel choose all
> c-files in zexy/src and hit "OK"
> - return to item-8 until you stop getting errors

> mind, that you must not use the dll while it is created (best close pd)

> if you want step-by-step instructions for vc7, vc2000, vc2006 and
> vc3000, please send them to me and i'll give it a go (dev-elitarism
> again)

> pd comes with some externals (e.g. the foo-stuff, or [fiddle~]) and uses
> makefiles to build these.
> for this to work, you have to setup your environment correctly:
-> first open the makefile (e.g. pd/doc/6.externs/makefile) with your
> favourite text-editor and correct all the paths that are wrong
> - VC6 came with a vc6vars.bat (ok the name is wrong but something along
> these lines; it was a .bat-file which would set your envirnment
> variables when run; more modern incarnations might do without the .bat
> - open the dosbox (the rest will happen within the dosbox)
> - run the vc6vars.bat (or however it is called) if this is needed for
> your compiler-incarnation
> - cd to your path (e.g. pd/doc/6.externs/)
> - run "nmake pd_nt"

> if nmake, cl, link cannot be found, you might want to add the paths to
> them to your PATH variable.

Martin Peach wrote:

> If you're on some kind of MSVC, you set up a project to build a dll, in
> "preprocessor defines" define MSW, in "additional include paths" include
> the path to pd/src/m_pd.h, link with pd.lib from pd/bin, and in the
> linker command line add "/export:yourexternal_setup" to export the setup
> function. All the other functions in your code can be static and don't
> need to be exported. After it builds you take the dll from the release
> folder and put it in your pd/extra folder.
> That should be everything you need, but if it's too cryptic I can go
> into more detail...

> Martin

I'm having trouble getting the helloworld external to compile properly on Windows.

The main resource is apparently this: HOWTO write an External for puredata, and some previous posts on this topic are here: Compiling new external, Max/MSP microtuning externals to convert to pd

Bear with me, because working with the C compiler is still rather mysterious to me, so I may be making some obvious mistakes. I've installed the djgpp compiler, and followed all the instructions as best as I could. I'm working on XP. I put "m_pd.h" (from the pd/src/ folder) and "helloworld.c" in the same folder and from that directory on the command line (in a DOS "Command Prompt" window) typed:

gcc -c helloworld.c -o helloworld.o

As far as I can tell, this successfully produced the "helloworld.o" object file in the same directory as the "helloworld.c" file. Then I typed:

ld -export_dynamic -shared -o helloworld.dll helloworld.o -lc -lm

Which, as I understand, is the "linking" step, and the only difference between this command and the command for linux is that ".pd_linux" is replaced with ".dll". Anyway, the compiler responded with:

c:/progra~1/djgpp/bin/ld.exe: -shared not supported

So, not having any other ideas, I tried omitting the -shared flag:

ld -export_dynamic -o helloworld.dll helloworld.o -lc -lm

That produced this response:

c:/progra~1/djgpp/bin/ld.exe: warning: cannot find entry symbol xport_dynamic; defaulting to 000018d0
helloworld.o:helloworld.c:(.text+0x1e): undefined reference to `post'
helloworld.o:helloworld.c:(.text+0x37): undefined reference to `pd_new'
helloworld.o:helloworld.c:(.text+0x60): undefined reference to `gensym'
helloworld.o:helloworld.c:(.text+0x79): undefined reference to `class_new'
helloworld.o:helloworld.c:(.text+0x96): undefined reference to `class_addbang'

Why is -shared not supported and what can I do to fix that? I tried Microsoft Visual C++ Express Edition, but found the interface bewildering. I don't think I could even find the words "compile" and "link" in any menu...

Then I looked in the "0.README" file located in the pd/doc/6.externs/ directory, and found this line (in reference to the 3 example enternals in that folder):

To compile, type "make pd_linux", "nmake pd_nt", "make pd_irix5" or "make pd_irix6".

If I wanted to compile these, where would I even type this? Is "nmake" an actual command?

Then I tried poking around the GNU info files, and saw some vague information about "binutils" and "dlltool" but it is so beyond me right now that I'm turning here. Could someone please enumerate the steps required to take the C source file "helloworld.c" and make it into a usable object in pd without skipping any steps? I (and I'm sure many others) would greatly appreciate that.

Thanks in advance!

SUBJECT: Need help with PD externals

Hi,

1. I have written some code in C/C++. I would now like to create a pd external and be able to run my C/C++ code in pd (windows environment). I would like my PD object to have say 3-4 inlets and 2-3 outlets.
   Furthermore at least one of the inlets would contain compound data, something like an array of 10-15 floats.
   Thus my external would be a bit more complex than the 'very basic one', which has a single float as inlet, & a single float as outlet.

2. I work in the windows environment (currently my operating environment has pentium machines with windows operating systems installed on them (windows XP, or windows 2000 Professional).
   I am using a the free DevCPP or DevC++ compiler (version 4.9.9.2) the IDE, (which uses the gnu C compiler MinGW at its base). Furthermore, I am using: Pd version 0.38.4-extended-RC8 (windows platform). I wonder if someone has already developed externals in a same (or similar, i.e. Windows) environment.

3. If someone has, can you please mail me a simple compilable code that you might have had prepared, and guide me through the exact steps which one must follow to make a pd external.

4. I wish to know, if in the Windows/DevCPP compiler environment, whether it is possbile to create a PD external without creating a dll in windows, or is it always necessary to first create a dll, even in the simplest case?

5. Last, but not the least, I must mention here that I don't have "a lot" of experience in pd, so I will appreciate if someone could explain things in an easy to understand style.
   But in any case, I will ask again, in case I don't understand something.
   I hope that should work.

Thanks and regards,

ps:

The following should actually have been posted as a separate thread, but since its related to the topic above, i continue to write it here:

In addition to what I have asked for above, I would also like some feedback on the following...

SUBJECT2: Creating/Compiling PD externals

My previous unsucessful attempts at creating/understanding the PD external:
I had tried to read through, and tried to implement the sample code in the tutorial, named:
"How to write an External for puredata" available at the iem site...

But I am facing a few problems, and here are some specific queries related to that:

A.) While in the windows environment, must one always need to create a dll first, or is it possible to create a PD external in any other way as well?

B.) If one must do it by first creating a dll, then the code as mentioned in the tutorial would need to be modified and can't just be copy+pasted & compiled directly. I.e.
One needs to paste the data declaration part in the header;
ii) Also one must declare all the subroutine (i.e. procedures/methods) names in the header file as well, while their definition or implementation goes in another main file, which must include our earlier created header file; and finally
iii) One must insert a special prefix before all the methods when are required for the dll...

Am I right about the 3 above mentioned points?

Thanks yet again,

I think the VASP library is designed for this kind of array manipulation.

http://grrrr.org/ext/vasp/

Otherwise, you can sum a sequence of incoming numbers like this:

numbers to sum (send one by one)
| reset sum (usually send 0)
| |
| |/connect to right outlet of the [t f f] below
[+]
|
[t f f]
| \connect to right inlet of the [+] above
sum

EDIT: oops, i just saw you are using signals not numbers...
http://www.puredata.org/Members/jb/ has flib with [++~] which says it sums the values in a signal block.

arrrrrgggg:

This is the GridFlow 0.8.0 configurator within Ruby version 1.8.2
[fast] Compile for speed (and not debuggability): enabled
[gcc3] GNU C++ Compiler 3: missing (undefined method `<' for nil:NilClass)
[stl] C++ Standard Template Library: missing (gcc compilation error)
[gcc64] GNU C++ in 64-bit mode: missing (gcc compilation error)
[libruby] Ruby as a dynamic library: missing (gcc compilation error)
[librubystatic] Ruby as a static library: missing (gcc compilation error)
[pentium] Pentium-compatible CPU: missing (gcc compilation error)
[mmx] MMX-compatible CPU (using NASM): disabled (would need pentium)
[simd] SIMD (MMX/SSE/Altivec) (using GCC): disabled (would need pentium)
[profiler] profiler (speed measurements): disabled (would need pentium)
[usb] USB Library: missing (where is usb.h ?)
[ieee1394] IEEE1394 Libraries for Linux (raw1394/dc1394): disabled (by author)
[x11] X11 Display Protocol: missing (where is X11/Xlib.h ?)
[x11_shm] X11 acceleration through shared memory: disabled (would need x11)
[sdl] Simple Directmedia Layer (experimental support): missing (where is SDL/SDL.h ?)
[objcpp] GNU/Apple ObjectiveC++ Compiler: missing (where is objc/Object.h ?)
[quartz] Apple Quartz/Cocoa Display: disabled (would need objcpp)
[aalib] Ascii Art Library: missing (where is aalib.h ?)
[jpeg] JPEG Library: missing (where is jpeglib.h ?)
[png] PNG Library <libpng12/png.h>: missing (where is libpng12/png.h ?)
[png] PNG Library <png.h>: missing (where is png.h ?)
[videodev] Video4linux Digitizer Driver Interface: missing (gcc compilation error)
[mpeg3] HeroineWarrior LibMPEG3 <libmpeg3/libmpeg3.h>: missing (where is libmpeg3/libmpeg3.h ?)
[mpeg3] HeroineWarrior LibMPEG3 <libmpeg3.h>: missing (where is libmpeg3.h ?)
[quicktimeapple] Apple's QuickTime: missing (gcc compilation error)
[quicktimehw] HeroineWarrior QuickTime4Linux (or LibQuickTime) (try #1): missing (gcc compilation error)
[quicktimehw] HeroineWarrior QuickTime4Linux (or LibQuickTime) (try #2): missing (gcc compilation error)
[xine] Xine movie decoder: disabled (by author)
[puredata] Miller Puckette's Pure Data: disabled (would need libruby or librubystatic)
generating ./config.make
generating config.h
creating Makefile

humm.... it will probably compile but seem will could do not much without jpeg png video4linux X11 etc....

will wait a .deb package...