void类型参数在C/C++中的不同

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在C语言中，void类型是没有问题，代码如下：main.c

#include <stdio.h>#include <string.h>#define GENERICvoid *MyStrcpy( void *dst, const void GENERIC *src, unsigned int len ){unsigned char *pDst;const unsigned char GENERIC *pSrc;pSrc = src;pDst = dst;while ( len-- )*pDst++ = *pSrc++;return ( pDst );}void main(){int i=1;int j=2;char d[]="123";char s[]="123456789";char d1[]="123";char s1[]="123456789";strcpy(d,s);printf("s=%s   d=%s\n",s,d);MyStrcpy(d1,s1,3);printf("d1=%s   s1=%s\n",s1,d1); printf("i=0X%08X\nj=0X%08X\ns=0X%08X\nd=0X%08X\ns1=0X%08X\nd1=0X%08X\nstrcpy=0X%08X\nprintf=0X%08X\n",&i,&j,s,d,s1,d1,strcpy,printf);}

而在C++中，我们要改成模板，代码如下：main.cpp

#include <stdio.h>#include <string.h>#define GENERICtemplate <typename T>void *MyStrcpy( T *dst, const T GENERIC *src, unsigned int len ){T *pDst;const T GENERIC *pSrc;pSrc = src;pDst = dst;while ( len-- )*pDst++ = *pSrc++;return ( pDst );}void main(){int i=0,j=1;char s[]="123456789";char d[]="123";char s1[]="123456789";char d1[]="123";strcpy(d,s);printf("s=%s   d=%s\n",s,d);MyStrcpy(d1,s1,3);printf("d1=%s   s1=%s\n",s1,d1); printf("i=0X%08X\nj=0X%08X\ns=0X%08X\nd=0X%08X\ns1=0X%08X\nd1=0X%08X\nstrcpy=0X%08X\nprintf=0X%08X\n",&i,&j,s,d,s1,d1,strcpy,printf);}

以上代码的功能是一样的，但是我们要进行不同的改变。上面是在VC++6.0编译环境下测试。