view src/usr/cat.c @ 21:45035047d186

use stdarg for printf
author mir3636
date Sat, 07 Apr 2018 18:44:18 +0900
parents 83c23a36980d
children
line wrap: on
line source

#include "types.h"
#include "stat.h"
#include "user.h"

char buf[512];

void
cat(int fd)
{
    int n;
    
    while((n = read(fd, buf, sizeof(buf))) > 0)
        write(1, buf, n);
    if(n < 0){
        printf(1, "cat: read error\n");
        exit();
    }
}

int
main(int argc, char *argv[])
{
    int fd, i;
    
    if(argc <= 1){
        cat(0);
        exit();
    }
    
    for(i = 1; i < argc; i++){
        if((fd = open(argv[i], 0)) < 0){
            printf(1, "cat: cannot open %s\n", argv[i]);
            exit();
        }
        cat(fd);
        close(fd);
    }
    exit();
}