滚动字幕的实现

demo1

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

int sleep(unsigned long x)
{
    clock_t c1 = clock(), c2;

    do {
        if ((c2 = clock()) == (clock_t)-1)
            return 0;
    } while (1000.0 * (c2 - c1) / CLOCKS_PER_SEC < x);
    return 1;
}

int main(void)
{
    int  i;
    int  cnt = 0;                    
    char name[] = "BohYoh ";        
    int  name_len = strlen(name);    

    while (1) {
        putchar('
');            

        for (i = 0; i < name_len; i++) {
            if (cnt + i < name_len)
                putchar(name[cnt + i]);
            else
                putchar(name[cnt + i - name_len]);
        }

        fflush(stdout);
        sleep(500);

        if (cnt < name_len - 1)
            cnt++;                    
        else
            cnt = 0;            
    }

    return 0;
}

demo2

#include <time.h>
#include <stdio.h>
#include <string.h>
int sleep(unsigned long x)
{
    clock_t c1 = clock(), c2;

    do {
        if ((c2 = clock()) == (clock_t)-1)    
            return 0;
    } while (1000.0 * (c2 - c1) / CLOCKS_PER_SEC < x);
    return 1;
}
int main(void)
{
    int  i;
    int  cnt = 0;                    
    char name[] = "BohYoh ";    
    int  name_len = strlen(name);

    while (1) {
        putchar('
');            

        for (i = 0; i < name_len; i++) {
            if (cnt + i < name_len)
                putchar(name[cnt + i]);
            else
                putchar(name[cnt + i - name_len]);
        }

        fflush(stdout);
        sleep(500);

        if (cnt > 0)
            cnt--;
        else
            cnt = name_len - 1;        
    }
    return 0;
}