linux中，c语言字符串比较采用strcmp()函数
在linux命令行下，man strcmp，可以看到函数说明：
$ man strcmp
...
NAME
strcmp, strncmp - compare two strings
SYNOPSIS
#include
int strcmp(const char *s1, const char *s2);
DESCRIPTION
The strcmp() function compares the two strings s1 and s2. It returns an integer less than, equal to, or greater than zero if s1 is found, respectively, to be less than, to match, or be greater than s2.
strcmp函数比较两个字符串s1和s2. 函数返回小于0，等于0，或大于0的整数，分别对应s1
比如 s1 = "good" s2="...this is good", 从s2取后四位进行两个字符串比较，代码如下：
#include
#include
int main()
{
char *s1 = "good" , *s2="...this is good" ;
int len=strlen(s2);
if ( len >= 4 ) //如果串长超过4位，则移动指针到最后四位的位置
s2 =s2+len-4;
printf("s2=%s\n", s2 ); //输出移位后的字符串内容
printf("compare s1,s2=%d\n", strcmp(s1,s2) ); //输出0，表示相同
return 0;
}
