1 /****************************************************************************
2 * Copyright 2020,2021 Thomas E. Dickey *
3 * Copyright 1998-2016,2017 Free Software Foundation, Inc. *
4 * *
5 * Permission is hereby granted, free of charge, to any person obtaining a *
6 * copy of this software and associated documentation files (the *
7 * "Software"), to deal in the Software without restriction, including *
8 * without limitation the rights to use, copy, modify, merge, publish, *
9 * distribute, distribute with modifications, sublicense, and/or sell *
10 * copies of the Software, and to permit persons to whom the Software is *
11 * furnished to do so, subject to the following conditions: *
12 * *
13 * The above copyright notice and this permission notice shall be included *
14 * in all copies or substantial portions of the Software. *
15 * *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS *
17 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF *
18 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. *
19 * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, *
20 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR *
21 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR *
22 * THE USE OR OTHER DEALINGS IN THE SOFTWARE. *
23 * *
24 * Except as contained in this notice, the name(s) of the above copyright *
25 * holders shall not be used in advertising or otherwise to promote the *
26 * sale, use or other dealings in this Software without prior written *
27 * authorization. *
28 ****************************************************************************/
29
30 /****************************************************************************
31 * Author: Zeyd M. Ben-Halim <zmbenhal@netcom.com> 1992,1995 *
32 * and: Eric S. Raymond <esr@snark.thyrsus.com> *
33 * and: Thomas E. Dickey 1996-on *
34 ****************************************************************************/
35
36 /*
37 * clear.c -- clears the terminal's screen
38 */
39
40 #define USE_LIBTINFO
41 #include <clear_cmd.h>
42 #include <tty_settings.h>
43
44 MODULE_ID("$Id: clear.c,v 1.24 2021/03/20 18:23:14 tom Exp $")
45
46 const char *_nc_progname = "clear";
47
48 static GCC_NORETURN void
usage(void)49 usage(void)
50 {
51 #define KEEP(s) s "\n"
52 static const char msg[] =
53 {
54 KEEP("")
55 KEEP("Options:")
56 KEEP(" -T TERM use this instead of $TERM")
57 KEEP(" -V print curses-version")
58 KEEP(" -x do not try to clear scrollback")
59 };
60 #undef KEEP
61 (void) fprintf(stderr, "Usage: %s [options]\n", _nc_progname);
62 fputs(msg, stderr);
63 ExitProgram(EXIT_FAILURE);
64 }
65
66 int
main(int argc GCC_UNUSED,char * argv[]GCC_UNUSED)67 main(
68 int argc GCC_UNUSED,
69 char *argv[]GCC_UNUSED)
70 {
71 TTY tty_settings;
72 int fd;
73 int c;
74 char *term;
75 bool opt_x = FALSE; /* clear scrollback if possible */
76
77 _nc_progname = _nc_rootname(argv[0]);
78 term = getenv("TERM");
79
80 while ((c = getopt(argc, argv, "T:Vx")) != -1) {
81 switch (c) {
82 case 'T':
83 use_env(FALSE);
84 use_tioctl(TRUE);
85 term = optarg;
86 break;
87 case 'V':
88 puts(curses_version());
89 ExitProgram(EXIT_SUCCESS);
90 case 'x': /* do not try to clear scrollback */
91 opt_x = TRUE;
92 break;
93 default:
94 usage();
95 /* NOTREACHED */
96 }
97 }
98 if (optind < argc)
99 usage();
100
101 fd = save_tty_settings(&tty_settings, FALSE);
102
103 setupterm(term, fd, (int *) 0);
104
105 ExitProgram((clear_cmd(opt_x) == ERR)
106 ? EXIT_FAILURE
107 : EXIT_SUCCESS);
108 }
109