#include <stddef.h>
#include <stdio.h>
#include <dirent.h>
#include <stdlib.h>
#include <unistd.h>

#define    BUFFSIZE    4096
int
main(void)
{
    int        n;
    char    buf[BUFFSIZE];
    while ((n = read(STDIN_FILENO, buf, BUFFSIZE)) > 0)
        if (write(STDOUT_FILENO, buf, n) != n)
            perror("write error");
    if (n < 0)
        perror("read error");
    exit(0);
}