gcc编译常见问题解决方法

1、 implicit declaration of function `sleep' 

#include <unistd.h> 

 

2、 implicit declaration of function ‘malloc’

#include<stdlib.h>

 

3、 implicit declaration of function `memcpy'

#include <string.h>

 

 

4、 implicit declaration of function ` inet_addr’

#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>

 

5、 suggest parentheses around assignment used as truth value

=改成==

6、 Multiple definition of

将变量声明放到.c