C warning“comparison between pointer and integer [enabled by default]”

  一个小程序

#include <stdio.h>

void PrintHello(void)
{
  char ptr[] = "Hello wordl";
  printf("%s\n",ptr);

  return;
}

char *GetString(char *dest,const char *src)
{
 char *temp = dest;

 while(*src != 'NULL')
    *dest++ = *src++;

 return temp;

}

报警告 warning“comparison between pointer and integer [enabled by default]”

~  

当src是char 类型到时候，应该用'\0' or 0;

 while(*src != '\0')