最近写了一个递归Makefile，目的是既可以实现子模块的单独编译，也可以不做任何修改就和整个程序的整体进行无缝衔接的编译。具体的思路是借助第三方文件，将子模块编译好的.o文件的路径自动写到config.mk文件中，在总控Makfile中只需要include这个config.mk就可以。单个模块的编译只需要cd到相应目录就可以进行本模块的单独编译，整个程序的编译也只需要cd到顶层目录，分别执行make config,make,make install就可以进行编译和安装。下面这个就是顶层Makefile
CROSS_COMPILE= #CC=/opt/arm-cross-compile/arm-2010.09/bin/arm-none-linux-gnueabi-gcc #CC=gcc CC=arm-linux-gnueabi-gcc D=-DDEBUG CFLAGS= -g -O3 $(D) export CC CFLAGS INCLUDE_DIR = $(shell cd ./common/include/; pwd) SUB_DIR= ./entry/ \ ./sqlite/ \ NFS_DIR:=~/nfs CORE_NAME = core $(shell touch config.mk) include ./config.mk all:$(OBJS) $(CC) $(CFLAGS) $^ -lpthread -L/home/jiang/nfs/usr/lib/ -lsqlite3 -o $(CORE_NAME) config: @echo "OBJS+=\\" > config.mk @for dir in $(SUB_DIR); \ do \ echo "\n"; \ $(MAKE) -C $$dir ; \ echo "\n"; \ done clean: $(RM) ./config.mk @for dir in $(SUB_DIR); \ do \ echo "\n"; \ $(MAKE) -C $$dir clean; \ echo "\n"; \ done install: cp $(CORE_NAME) $(NFS_DIR)下面这个就是每一个子模块的Makfile，会把编译成功的.o文件路径添加到config.mk中
CUR_DIR=$(shell pwd) OBJ_DIR:=$(CUR_DIR)/obj INCLUDE_DIR= -I ./include -I ../common/include SRC=https://www.linuxidc.com/$(wildcard ./src/*.c) all:$(SRC) $(CC) $(CFLAGS) $(INCLUDE_DIR) -c $^ mv ./*.o $(OBJ_DIR) echo "${OBJ_DIR}/*.o \\" >> ../config.mk echo "\033[44;37m $(notdir $(CUR_DIR)) done \033[0m" clean: $(RM) $(OBJ_DIR)/*下面就是config.mk的内容，会在顶层目录中执行make config之后自动生成
OBJS+=\ /home/jiang/Documents/Documents/IntellStorage/A9_main/A9_core/entry/obj/*.o \ /home/jiang/Documents/Documents/IntellStorage/A9_main/A9_core/sqlite/obj/*.o \为了使一个头文件的实例在整个工程中只有一份，对于接口文件，约定一律以inter_开头进行命名并且放置在自己的include目录中，下面这个脚本的作用就是扫描指定的子模块的include目录，将其中的inter_*头文件在entry模块的include中自动生成同名符号链接文件。
#|/bin/bash #扫描指定include的文件，符合inter_*.h的文件会自动在entry/include中创建其符号链接 SHELL_DIR=$(cd $(dirname ${0});pwd) cd ${SHELL_DIR} SUB_INCLUDES="../camera/include ../buzzer/include ../gsm/include ../led/include ../sqlite/include ../zigbee/include" for A_SUB_INCLUDE in ${SUB_INCLUDES} do echo ${A_SUB_INCLUDE} ( cd ${A_SUB_INCLUDE} HEADERS=$(ls ./inter*) for A_HEADER in ${HEADERS} do ln -s ../${A_SUB_INCLUDE}/${A_HEADER} ../../entry/include/${A_HEADER} done ) done