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/*
* *****************************************************************************
*
* SPDX-License-Identifier: BSD-2-Clause
*
* Copyright (c) 2018-2021 Gavin D. Howard and contributors.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
* *****************************************************************************
*
* The bc help text.
*
*/
usage: %s [options] [file...]
bc is a command-line, arbitrary-precision calculator with a Turing-complete
language. For details, use `man %s` or see the online documentation at
https://git.yzena.com/gavin/bc/src/tag/%s/manuals/bc/%s.1.md.
This bc is compatible with both the GNU bc and the POSIX bc spec. See the GNU bc
manual (https://www.gnu.org/software/bc/manual/bc.html) and bc spec
(http://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html)
for details.
This bc has three differences to the GNU bc:
1) Arrays can be passed to the builtin "length" function to get the number of
elements currently in the array. The following example prints "1":
a[0] = 0
length(a[])
2) The precedence of the boolean "not" operator (!) is equal to that of the
unary minus (-), or negation, operator. This still allows POSIX-compliant
scripts to work while somewhat preserving expected behavior (versus C) and
making parsing easier.
3) This bc has many more extensions than the GNU bc does. For details, see the
man page or online documentation.
This bc also implements the dot (.) extension of the BSD bc.
Options:
-e expr --expression=expr
Run "expr" and quit. If multiple expressions or files (see below) are
given, they are all run before executing from stdin.
-f file --file=file
Run the bc code in "file" and exit. See above as well.
-g --global-stacks
Turn scale, ibase, and obase into stacks. This makes the value of each be
be restored on returning from functions. See the man page or online
documentation for more details.
-h --help
Print this usage message and exit.
-i --interactive
Force interactive mode.
-l --mathlib
Use predefined math routines:
s(expr) = sine of expr in radians
c(expr) = cosine of expr in radians
a(expr) = arctangent of expr, returning radians
l(expr) = natural log of expr
e(expr) = raises e to the power of expr
j(n, x) = Bessel function of integer order n of x
This bc may load more functions with these options. See the manpage or
online documentation for details.
-P --no-prompt
Disable the prompts in interactive mode.
-R --no-read-prompt
Disable the read prompt in interactive mode.
-r keyword --redefine=keyword
Redefines "keyword" and allows it to be used as a function, variable, and
array name. This is useful when this bc gives parse errors on scripts
meant for other bc implementations.
Only keywords that are not in the POSIX bc spec may be redefined.
It is a fatal error to attempt to redefine a keyword that cannot be
redefined or does not exist.
-q --quiet
Don't print version and copyright.
-s --standard
Error if any non-POSIX extensions are used.
-w --warn
Warn if any non-POSIX extensions are used.
-v --version
Print version information and copyright and exit.
Environment variables:
POSIXLY_CORRECT
Error if any non-POSIX extensions are used.
BC_ENV_ARGS
Command-line arguments to use on every run.
BC_LINE_LENGTH
If an integer, the number of characters to print on a line before
wrapping.
BC_BANNER
If an integer and non-zero, display the copyright banner in interactive
mode.
Overrides the default, which is %s print the banner.
BC_SIGINT_RESET
If an integer and non-zero, reset on SIGINT, rather than exit, when in
interactive mode.
Overrides the default, which is %s.
BC_TTY_MODE
If an integer and non-zero, enable TTY mode when it is available.
Overrides the default, which is TTY mode %s.
BC_PROMPT
If an integer and non-zero, enable prompt when TTY mode is possible.
Overrides the default, which is prompt %s.