1/* 2 * ***************************************************************************** 3 * 4 * SPDX-License-Identifier: BSD-2-Clause 5 * 6 * Copyright (c) 2018-2021 Gavin D. Howard and contributors. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions are met: 10 * 11 * * Redistributions of source code must retain the above copyright notice, this 12 * list of conditions and the following disclaimer. 13 * 14 * * Redistributions in binary form must reproduce the above copyright notice, 15 * this list of conditions and the following disclaimer in the documentation 16 * and/or other materials provided with the distribution. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 19 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE 22 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 23 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 24 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 25 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 26 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 27 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 28 * POSSIBILITY OF SUCH DAMAGE. 29 * 30 * ***************************************************************************** 31 * 32 * The dc help text. 33 * 34 */ 35 36usage: %s [options] [file...] 37 38dc is a reverse-polish notation command-line calculator which supports unlimited 39precision arithmetic. For details, use `man %s` or see the online documentation 40at https://git.yzena.com/gavin/bc/src/tag/%s/manuals/bc/%s.1.md. 41 42This dc is (mostly) compatible with the OpenBSD dc and the GNU dc. See the 43OpenBSD man page (http://man.openbsd.org/OpenBSD-current/man1/dc.1) and the GNU 44dc manual (https://www.gnu.org/software/bc/manual/dc-1.05/html_mono/dc.html) 45for details. 46 47This dc has a few differences from the two above: 48 49 1) When printing a byte stream (command "P"), this bc follows what the FreeBSD 50 dc does. 51 2) This dc implements the GNU extensions for divmod ("~") and modular 52 exponentiation ("|"). 53 3) This dc implements all FreeBSD extensions, except for "J" and "M". 54 4) This dc does not implement the run command ("!"), for security reasons. 55 5) Like the FreeBSD dc, this dc supports extended registers. However, they are 56 implemented differently. When it encounters whitespace where a register 57 should be, it skips the whitespace. If the character following is not 58 a lowercase letter, an error is issued. Otherwise, the register name is 59 parsed by the following regex: 60 61 [a-z][a-z0-9_]* 62 63 This generally means that register names will be surrounded by whitespace. 64 65 Examples: 66 67 l idx s temp L index S temp2 < do_thing 68 69 Also note that, unlike the FreeBSD dc, extended registers are not even 70 parsed unless the "-x" option is given. Instead, the space after a command 71 that requires a register name is taken as the register name. 72 73Options: 74 75 -e expr --expression=expr 76 77 Run "expr" and quit. If multiple expressions or files (see below) are 78 given, they are all run. After running, dc will exit. 79 80 -f file --file=file 81 82 Run the dc code in "file" and exit. See above. 83 84 -h --help 85 86 Print this usage message and exit. 87 88 -i --interactive 89 90 Put dc into interactive mode. See the man page for more details. 91 92 -P --no-prompt 93 94 Disable the prompts in interactive mode. 95 96 -R --no-read-prompt 97 98 Disable the read prompt in interactive mode. 99 100 -V --version 101 102 Print version and copyright and exit. 103 104 -x --extended-register 105 106 Enable extended register mode. 107