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 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 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