xref: /freebsd/contrib/bc/gen/bc_help.txt (revision f7c32ed617858bcd22f8d1b03199099d50125721)
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 bc help text.
33 *
34 */
35
36usage: %s [options] [file...]
37
38bc is a command-line, arbitrary-precision calculator with a Turing-complete
39language. For details, use `man %s` or see the online documentation at
40https://git.yzena.com/gavin/bc/src/tag/%s/manuals/bc/%s.1.md.
41
42This bc is compatible with both the GNU bc and the POSIX bc spec. See the GNU bc
43manual (https://www.gnu.org/software/bc/manual/bc.html) and bc spec
44(http://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html)
45for details.
46
47This bc has three differences to the GNU bc:
48
49  1) Arrays can be passed to the builtin "length" function to get the number of
50     elements currently in the array. The following example prints "1":
51
52       a[0] = 0
53       length(a[])
54
55  2) The precedence of the boolean "not" operator (!) is equal to that of the
56     unary minus (-), or negation, operator. This still allows POSIX-compliant
57     scripts to work while somewhat preserving expected behavior (versus C) and
58     making parsing easier.
59  3) This bc has many more extensions than the GNU bc does. For details, see the
60     man page or online documentation.
61
62This bc also implements the dot (.) extension of the BSD bc.
63
64Options:
65
66  -e  expr  --expression=expr
67
68      Run "expr" and quit. If multiple expressions or files (see below) are
69      given, they are all run before executing from stdin.
70
71  -f  file  --file=file
72
73      Run the bc code in "file" and exit. See above as well.
74
75  -g  --global-stacks
76
77      Turn scale, ibase, and obase into stacks. This makes the value of each be
78      be restored on returning from functions. See the man page or online
79      documentation for more details.
80
81  -h  --help
82
83      Print this usage message and exit.
84
85  -i  --interactive
86
87      Force interactive mode.
88
89  -L  --no-line-length
90
91      Disable line length checking.
92
93  -l  --mathlib
94
95      Use predefined math routines:
96
97          s(expr)  =  sine of expr in radians
98          c(expr)  =  cosine of expr in radians
99          a(expr)  =  arctangent of expr, returning radians
100          l(expr)  =  natural log of expr
101          e(expr)  =  raises e to the power of expr
102          j(n, x)  =  Bessel function of integer order n of x
103
104      This bc may load more functions with these options. See the manpage or
105      online documentation for details.
106
107  -P  --no-prompt
108
109      Disable the prompts in interactive mode.
110
111  -R  --no-read-prompt
112
113      Disable the read prompt in interactive mode.
114
115  -r  keyword  --redefine=keyword
116
117      Redefines "keyword" and allows it to be used as a function, variable, and
118      array name. This is useful when this bc gives parse errors on scripts
119      meant for other bc implementations.
120
121      Only keywords that are not in the POSIX bc spec may be redefined.
122
123      It is a fatal error to attempt to redefine a keyword that cannot be
124      redefined or does not exist.
125
126  -q  --quiet
127
128      Don't print version and copyright.
129
130  -s  --standard
131
132      Error if any non-POSIX extensions are used.
133
134  -w  --warn
135
136      Warn if any non-POSIX extensions are used.
137
138  -v  --version
139
140      Print version information and copyright and exit.
141
142  -z  --leading-zeroes
143
144      Enable leading zeroes on numbers greater than -1 and less than 1.
145
146Environment variables:
147
148  POSIXLY_CORRECT
149
150      Error if any non-POSIX extensions are used.
151
152  BC_ENV_ARGS
153
154      Command-line arguments to use on every run.
155
156  BC_LINE_LENGTH
157
158      If an integer, the number of characters to print on a line before
159      wrapping. Using 0 will disable line length checking.
160
161  BC_BANNER
162
163      If an integer and non-zero, display the copyright banner in interactive
164      mode.
165
166      Overrides the default, which is %s print the banner.
167
168  BC_SIGINT_RESET
169
170      If an integer and non-zero, reset on SIGINT, rather than exit, when in
171      interactive mode.
172
173      Overrides the default, which is %s.
174
175  BC_TTY_MODE
176
177      If an integer and non-zero, enable TTY mode when it is available.
178
179      Overrides the default, which is TTY mode %s.
180
181  BC_PROMPT
182
183      If an integer and non-zero, enable prompt when TTY mode is possible.
184
185      Overrides the default, which is prompt %s.
186