函数名: strrchr 
 功  能: 在串中查找指定字符的最后一个出现 
 用  法: #include <string.h> 
         char *strrchr(char *str, char c); 
 程序例: 
#include <string.h> 
 #include <stdio.h> 
int main(void) 
 { 
    char string[15]; 
    char *ptr, c = 'r'; 
   strcpy(string, "This is a string"); 
    ptr = strrchr(string, c); 
    if (ptr) 
       printf("The character %c is at position: %d\n", c, ptr-string); 
    else 
       printf("The character was not found\n"); 
    return 0; 
 }