This is a sample makefile which compile a GTK+ based program:
# basic GTK+ app makefile
SOURCES = myprg.c foo.c bar.c
OBJS = ${SOURCES:.c=.o}
CFLAGS = `gtk-config --cflags`
LDADD = `gtk-config --libs`
CC = gcc
PACKAGE = myprg
all : ${OBJS}
${CC} -o ${PACKAGE} ${OBJS} ${LDADD}
.c.o:
${CC} ${CFLAGS} -c $<
# end of fileFor more information about the make utility, you should read either the related man page or the relevant info file.