help needed to compile a C program

[macports at parvis.nl]

> On 2018-04-13, at 20:17, Rainer Müller <raimue at macports.org> wrote:
> 
> On 2018-04-13 18:21, macports at parvis.nl wrote:
>> with makefile:
>> ---
>> pango-list-typefaces:   pango-list-typefaces.c
>>         cc -o $@ -Wall -g pango-list-typefaces.c \
>>         $(pkg-config --cflags --libs pango) \
>>         $(pkg-config --cflags --libs cairo) \
>>         $(pkg-config --cflags --libs pangocairo) \Currently 
>>         $(pkg-config --cflags --libs glib-2.0)
> 
> The Makefile is your problem. $(foo) is a normal variable expansion.
> This should be: $(shell pkg-config ...)
> 
> Rainer

my mistake: I changed `pkg-config ..` to $(..).
but neither $(shell pkg-config nor `pkg-config helped. same error.
question remains open.

any suggestions on my aother questions?

Currently I have glib2 installed, but there is also glib2-devel, and they conflict with each other.
Same for pango and pango-devel.
- What is the difference?
- Which should I use?

I don't know what the include path will be. 
- How should I use 'port provides glib.h' ?