<string.h>的学习

感觉学习代码库最好的方法就是运行一下。

下面附上结果和示例代码 

#include <stdio.h>
#include <string.h>

int main(){
    const char * cs="Hello World";
    const char * ct="Hello";
    char * s=malloc(20);
    memset(s,0,20);
    char * t;
    int c='o';
    const size_t n=3;
    //strcpy(s,ct);
    printf("const char * cs=Hello World;\n\
    const char * ct=Hello;\n\
    int c=o;\n\
    const size_t n=3;\n\
    ");
    printf("=============================================\n");
    printf("\tthe result of strcpy(s,ct) is: %s\n",strcpy(s,ct));
    t=strncpy(s,ct,n);
    *(t+n)='\0';
    printf("\tthe result of char * strncpy(s,ct,n) is: %s\n",t);
    memcpy(s,ct,strlen(ct));//copy ct to s
    printf("\tthe result of char * strcat(s,ct) is: %s\n",strcat(s,ct));
    printf("\tthe result of char * strchr(cs,c) is: %s\n",strchr(cs,c));
    printf("\tthe result of char * strrchr(cs,c) is: %s\n",strrchr(cs,c));
    printf("\tthe result of size_t strspn(cs,ct) is: %d\n",strspn(cs,ct));
    printf("\tthe result of char * strpbrk(cs,ct) is: %s\n",strpbrk(cs,ct));
    printf("\tthe result of size_t strlen(cs) is: %d\n",strlen(cs));
}

 结果如下：