[PD] Problem compiling hello world external

[Jamie Bullock]

Dear list,

I am thinking of writing a few PD externals, and so decided to try the 
HOW-TO tutorial at http://iem.kug.ac.at/pd/externals-HOWTO/node1.html.

I am using gcc 3.3.3. m_pd.h is version 0.37 and is in /usr/include.

The problem is that if I simply copy and paste the helloworld code into  
a text  editor and try to compile with something like:

gcc helloworld_pd.c -o  helloworld.pd_linux -l/usr/include

It fails with the wollowing output:

 /usr/lib/gcc-lib/i386-redhat-linux/3.3.3/../../../crt1.o(.text+0x18): 
In function `_start':
: undefined reference to `main'
/tmp/ccWU3J7M.o(.text+0xf): In function `helloworld_bang':
: undefined reference to `post'
/tmp/ccWU3J7M.o(.text+0x28): In function `helloworld_new':
: undefined reference to `pd_new'
/tmp/ccWU3J7M.o(.text+0x53): In function `helloworld_setup':
: undefined reference to `gensym'
/tmp/ccWU3J7M.o(.text+0x5c): In function `helloworld_setup':
: undefined reference to `class_new'
/tmp/ccWU3J7M.o(.text+0x77): In function `helloworld_setup':
: undefined reference to `class_addbang'
collect2: ld returned 1 exit status

I apologise in advance if this question has already been answered - I 
couldn't find anything in the mail archives...

Any help would be appreciated.

Jamie
www.postlude.co.uk