字符串连接返回串尾

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

char *myStpcpy(char *des, const char *src);

int
main(void)
{
    char res[20];
    char *to = res;
    to = myStpcpy(to, "hello");
    to = myStpcpy(to, " world\n");

    printf(res);

    return 0;
}

char *
myStpcpy(char *des, const char *src)
{
    if (NULL == des || NULL == src)
        return NULL;

    char *d = des;
    const char *s = src;

    do
        *d++ = *s;
    while (*s++ != '\0');

    return (d - 1);
}

• 方便字符串连接。