====== Makefiles ======

Makefiles are very useful to automate compilation of multi-file projects in c/c++ with Linux.

===== Syntax =====
  * variables: 
<code>
<VARIABLE>=<string> # init
$(<VARIABLE>)       # get content
</code>

  * targets:
<code>
<target>: <prerequisite-targets>
	<code-to-execute>
</code>

  * template targets:
<code>
%.o:%.cpp
	<code-to-execute>
</code>

  * automatic variables ([[http://www.gnu.org/software/make/manual/make.html#Automatic-Variables|complete list]])::
    * ''$@'' : target
    * ''$^'' : list of requirements
    * ''$<'' : first requirement
    * ''$(MAKECMDGOALS)'' : make argument

  * functions ([[http://www.gnu.org/software/make/manual/make.html#Functions|complete list]]):
    * ''$(subst from,to,text)''
    * ''$(filter-out <list>, <list>)''

  * **Mini Example**
<code>
COMPILO=g++
SRCSCPP = $(wildcard src/*.cpp)
OBJS = $(patsubst %.cpp,build/%.o,$(notdir $(SRCSCPP)))
prog: $(OBJS)
	$(COMPILO) -o build/$@ $(OBJS)
build/%.o:%.cpp
	$(COMPILO) -c -o $@ $^
</code>


===== Example =====

<code makefile>
INCLUDE= \
	-I/usr/include \
	-I/usr/local/include \
	-I. \
	`pkg-config --cflags libglade-2.0` 

BIN_PATH=./

LIBS= \
	`pkg-config --libs libglade-2.0` \
	`pkg-config --libs gtk+-2.0` \
	-export-dynamic

LIBS_PATH= \
	-L/lib \
	-L/usr/lib \
	-L/usr/local/lib \
	-L.

COMPILO=g++

FLAGS= -c -g -Wall -ansi -pedantic
#FLAGS= -c -ansi -pedantic

OBJ= \
	file1.o \
	file2.o



	
# cibles :

monprog: $(OBJ)
	$(COMPILO) -o $(BIN_PATH)monprog $(OBJ) $(LIBS_PATH) $(LIBS)

clean : 
	rm -f *.o

clear : 
	rm -f *.o monprog

# compilation des sources :

file1.o : file1.cpp file1.h
	$(COMPILO) $(FLAGS) $(INCLUDE) -o file1.o file1.cpp

file2.o : file2.cpp file2.h
	$(COMPILO) $(FLAGS) $(INCLUDE) -o file2.o file2.cpp
</code>


===== pkg-config =====


When using libraries, pkg-config is very useful :
<code>
pkg-config --cflags libxml++-2.6
pkg-config --libs libxml++-2.6
</code>


===== auto-tools =====