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Serenity Operating System
1/*
2 * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are met:
7 *
8 * 1. Redistributions of source code must retain the above copyright notice, this
9 * list of conditions and the following disclaimer.
10 *
11 * 2. Redistributions in binary form must reproduce the above copyright notice,
12 * this list of conditions and the following disclaimer in the documentation
13 * and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
16 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
18 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
21 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
22 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
23 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
24 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27#include <fcntl.h>
28#include <stdio.h>
29#include <sys/ioctl.h>
30#include <unistd.h>
31
32static int key_fd;
33
34void wait_for_key()
35{
36 printf("\033[7m--[ more ]--\033[0m");
37 fflush(stdout);
38 char dummy;
39 read(key_fd, &dummy, 1);
40 printf("\n");
41}
42
43int main(int argc, char** argv)
44{
45 (void)argc;
46 (void)argv;
47
48 if (pledge("stdio rpath tty", nullptr) < 0) {
49 perror("pledge");
50 return 1;
51 }
52
53 key_fd = STDOUT_FILENO;
54
55 struct winsize ws;
56 ioctl(1, TIOCGWINSZ, &ws);
57
58 if (pledge("stdio", nullptr) < 0) {
59 perror("pledge");
60 return 1;
61 }
62
63 unsigned lines_printed = 0;
64 while (!feof(stdin)) {
65 char buffer[BUFSIZ];
66 auto* str = fgets(buffer, sizeof(buffer), stdin);
67 if (!str)
68 break;
69 printf("%s", str);
70 ++lines_printed;
71 if ((lines_printed % (ws.ws_row - 1)) == 0) {
72 wait_for_key();
73 }
74 }
75
76 close(key_fd);
77 return 0;
78}