1/* See LICENSE file for copyright and license details. */
 2
 3
 4#include <fcntl.h>
 5#include <signal.h>
 6#include <unistd.h>
 7
 8#include "util.h"
 9
10static void
11usage(void)
12{
13	eprintf("usage: %s [-ai] [file ...]\n", argv0);
14}
15
16// ?man tee: duplicate input
17// ?man arguments: file ...
18// ?man read from standard input and write to standard output and files
19int
20main(int argc, char *argv[])
21{
22	int *fds = NULL;
23	size_t i, nfds;
24	ssize_t n;
25	int ret = 0, aflag = O_TRUNC, iflag = 0;
26	char buf[BUFSIZ];
27
28	ARGBEGIN {
29	// ?man -a: print or show all entries
30	case 'a':
31		aflag = O_APPEND;
32		break;
33	// ?man -i: interactive mode or prompt for confirmation
34	case 'i':
35		iflag = 1;
36		break;
37	default:
38		usage();
39	} ARGEND
40
41	if (iflag && signal(SIGINT, SIG_IGN) == SIG_ERR)
42		eprintf("signal:");
43	nfds = argc + 1;
44	fds = ecalloc(nfds, sizeof(*fds));
45
46	for (i = 0; i < (size_t)argc; i++) {
47		if ((fds[i] = open(argv[i], O_WRONLY|O_CREAT|aflag, 0666)) < 0) {
48			weprintf("open %s:", argv[i]);
49			ret = 1;
50		}
51	}
52	fds[i] = 1;
53
54	while ((n = read(0, buf, sizeof(buf))) > 0) {
55		for (i = 0; i < nfds; i++) {
56			if (fds[i] >= 0 && writeall(fds[i], buf, n) < 0) {
57				weprintf("write %s:", (i != (size_t)argc) ? argv[i] : "<stdout>");
58				fds[i] = -1;
59				ret = 1;
60			}
61		}
62	}
63	if (n < 0)
64		eprintf("read <stdin>:");
65
66	return ret;
67}