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{{ A H N HN }} 75 76 -E seed --seed=seed 77 78 Sets the builtin variable seed to the given value assuming that the given 79 value is in base 10. It is a fatal error if the given value is not a valid 80 number. 81{{ end }} 82 83 -e expr --expression=expr 84 85 Run "expr" and quit. If multiple expressions or files (see below) are 86 given, they are all run. After running, dc will exit. 87 88 -f file --file=file 89 90 Run the dc code in "file" and exit. See above. 91 92 -h --help 93 94 Print this usage message and exit. 95 96 -I ibase --ibase=ibase 97 98 Sets the builtin variable ibase to the given value assuming that the given 99 value is in base 10. It is a fatal error if the given value is not a valid 100 number. 101 102 -i --interactive 103 104 Put dc into interactive mode. See the man page for more details. 105 106 -L --no-line-length 107 108 Disable line length checking. 109 110 -O obase --obase=obase 111 112 Sets the builtin variable obase to the given value assuming that the given 113 value is in base 10. It is a fatal error if the given value is not a valid 114 number. 115 116 -P --no-prompt 117 118 Disable the prompts in interactive mode. 119 120 -R --no-read-prompt 121 122 Disable the read prompt in interactive mode. 123 124 -S scale --scale=scale 125 126 Sets the builtin variable scale to the given value assuming that the given 127 value is in base 10. It is a fatal error if the given value is not a valid 128 number. 129 130 -V --version 131 132 Print version and copyright and exit. 133 134 -x --extended-register 135 136 Enable extended register mode. 137 138 -z --leading-zeroes 139 140 Enable leading zeroes on numbers greater than -1 and less than 1. 141 142Environment variables: 143 144 DC_ENV_ARGS 145 146 Command-line arguments to use on every run. 147 148 DC_LINE_LENGTH 149 150 If an integer, the number of characters to print on a line before 151 wrapping. Using 0 will disable line length checking. 152 153 DC_SIGINT_RESET 154 155 If an integer and non-zero, reset on SIGINT, rather than exit, when in 156 interactive mode. 157 158 Overrides the default, which is %s. 159 160 DC_TTY_MODE 161 162 If an integer and non-zero, enable TTY mode when it is available. 163 164 Overrides the default, which is TTY mode %s. 165 166 DC_PROMPT 167 168 If an integer and non-zero, enable prompt when TTY mode is possible. 169 170 Overrides the default, which is prompt %s. 171 172 DC_EXPR_EXIT 173 174 If an integer and non-zero, exit when expressions or expression files are 175 given on the command-line, and does not exit when an integer and zero. 176 177 Overrides the default, which is %s. 178