C语言下的ip与long之间的互换(long2ip,ip2long)

#include <stdio.h> 

//--------------------------------------------------------------------- 
unsigned long ip2long(const char* ip){ 
  unsigned char a, b, c, d; 
  sscanf(ip, "%hhu.%hhu.%hhu.%hhu", &a, &b, &c, &d); 
  return ((a << 24) | (b << 16) | (c << 8) | d); 
} 

//--------------------------------------------------------------------- 
void long2ip(unsigned long ip, char buf[]){ 
  int i = 0; 
  unsigned long tmp[4] = {0}; 

  for(i = 0; i < 4; i++){ 
    tmp[i] = ip & 255; 
    ip = ip >> 8; 
  } 
  sprintf(buf, "%lu.%lu.%lu.%lu", tmp[3], tmp[2], tmp[1], tmp[0]); 
} 

//--------------------------------------------------------------------- 
int main(){ 
  char* ip = "192.168.1.2"; 
  char buf[16] = {0}; 
  unsigned long ip_long = 0; 

  ip_long = ip2long(ip); 
  printf("%lu\n", ip_long); 
   
  long2ip(ip_long, buf); 
  puts(buf); 

  return 0; 
} 

#include <stdio.h>

#include <winsock.h>

char *long2ip(u_long in);
u_long ip2long(char *ip);

int main()
{
    char p[16];
    printf("请输入IP地址:\n");
    scanf("%s",p);
    u_long l = ip2long(p);
    printf("%s\n",long2ip(l));
    int inum = 0 ;
    scanf("%d",inum);
    return 0;
}

char *long2ip(u_long in)
{
    u_char *p;
    p = (u_char*)(&in);
    static char output[16];
    _snprintf_s(output,16,16,"%d.%d.%d.%d",p[0],p[1],p[2],p[3]);
    return output;
}

u_long ip2long(char *ip)
{
    u_char addr[16];
    sscanf(ip,"%d.%d.%d.%d",addr,addr+1,addr+2,addr+3);
    u_long *vl = (u_long*)(&addr);
    return *vl;
}