| 1 | #include "types.h" |
| 2 | #include "stat.h" |
| 3 | #include "user.h" |
| 4 | |
| 5 | char buf[512]; |
| 6 | |
| 7 | void |
| 8 | cat(int fd) |
| 9 | { |
| 10 | int n; |
| 11 | |
| 12 | while((n = read(fd, buf, sizeof(buf))) > 0) { |
| 13 | if (write(1, buf, n) != n) { |
| 14 | printf(1, "cat: write error\n" ); |
| 15 | exit(); |
| 16 | } |
| 17 | } |
| 18 | if(n < 0){ |
| 19 | printf(1, "cat: read error\n" ); |
| 20 | exit(); |
| 21 | } |
| 22 | } |
| 23 | |
| 24 | int |
| 25 | main(int argc, char *argv[]) |
| 26 | { |
| 27 | int fd, i; |
| 28 | |
| 29 | if(argc <= 1){ |
| 30 | cat(0); |
| 31 | exit(); |
| 32 | } |
| 33 | |
| 34 | for(i = 1; i < argc; i++){ |
| 35 | if((fd = open(argv[i], 0)) < 0){ |
| 36 | printf(1, "cat: cannot open %s\n" , argv[i]); |
| 37 | exit(); |
| 38 | } |
| 39 | cat(fd); |
| 40 | close(fd); |
| 41 | } |
| 42 | exit(); |
| 43 | } |
| 44 | |