view uprogs/cat.c @ 0:c450faca55f4

Init
author Tatsuki IHA <innparusu@cr.ie.u-ryukyu.ac.jp>
date Sun, 22 Oct 2017 18:25:39 +0900
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#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();
}