Linux头文件引用小技巧

0.需求：
将本地头文件引用，#include "test.h"更换为#include <test.h>系统引用方式.

1.目录结构如下
 ├── Makefile
├── include
│   └── test.h
└── main.c
# mkdir include 
# emnacs test.h
#include <stdio.h>
int add(int a, int b){
  printf("%s(), line = %d, a = %d, b = %d\n",__FUNCTION__,__LINE__,a,b);
  return (a + b);
}

2.main.c
#include <test.h>
//#include "test.h"
//#include "./include/test.h"
int main(){
  int sum;
  sum = add(11,12);
  printf("%s(), line = %d, sum = %d\n",__FUNCTION__,__LINE__,sum);
}

3.Makefile
$(CC) = gcc
CFLAGS=-I./include

.PHONY:clean #增加
all:main
main:   main.c
        $(CC) $(CFLAGS) -o $@ $^
clean:
        rm main