if (memcmp(OK,buffer,4)!=0) 新手求教育

if (memcmp(OK,buffer,4)!=0) 新手求教育

#include int memcmp( const void *buffer1,const void *buffer2,size_t count );
功能：函数比较buffer1和buffer2的前count个字符.返回值如下:
Value
less than 0
buffer1 is less than buffer2
equal to 0
buffer1 is equal to buffer2
greater than 0
buffer1 is greater than buffer2