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36 usage: %s [options] [file...]
38 dc is a reverse-polish notation command-line calculator which supports unlimited
39 precision arithmetic. For details, use `man %s` or see the online documentation
40 at https://git.gavinhoward.com/gavin/bc/src/tag/%s/manuals/bc/%s.1.md.
42 This dc is (mostly) compatible with the OpenBSD dc and the GNU dc. See the
43 OpenBSD man page (http://man.openbsd.org/OpenBSD-current/man1/dc.1) and the GNU
44 dc manual (https://www.gnu.org/software/bc/manual/dc-1.05/html_mono/dc.html)
47 This dc has a few differences from the two above:
49 1) When printing a byte stream (command "P"), this bc follows what the FreeBSD
51 2) This dc implements the GNU extensions for divmod ("~") and modular
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:
63 This generally means that register names will be surrounded by whitespace.
67 l idx s temp L index S temp2 < do_thing
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.
77 Disables clamping of digits that are larger than or equal to the current
78 ibase when parsing numbers.
80 This means that the value added to a number from a digit is always that
81 digit's value multiplied by the value of ibase raised to the power of the
82 digit's position, which starts from 0 at the least significant digit.
84 If multiple of this option and the -c option are given, the last is used.
88 Enables clamping of digits that are larger than or equal to the current
89 ibase when parsing numbers.
91 This means that digits that the value added to a number from a digit that
92 is greater than or equal to the ibase is the value of ibase minus 1 all
93 multiplied by the value of ibase raised to the power of the digit's
94 position, which starts from 0 at the least significant digit.
96 If multiple of this option and the -C option are given, the last is used.
101 Sets the builtin variable seed to the given value assuming that the given
102 value is in base 10. It is a fatal error if the given value is not a valid
106 -e expr --expression=expr
108 Run "expr" and quit. If multiple expressions or files (see below) are
109 given, they are all run. After running, dc will exit.
113 Run the dc code in "file" and exit. See above.
117 Print this usage message and exit.
119 -I ibase --ibase=ibase
121 Sets the builtin variable ibase to the given value assuming that the given
122 value is in base 10. It is a fatal error if the given value is not a valid
127 Put dc into interactive mode. See the man page for more details.
131 Disable line length checking.
133 -O obase --obase=obase
135 Sets the builtin variable obase to the given value assuming that the given
136 value is in base 10. It is a fatal error if the given value is not a valid
141 Disable the prompts in interactive mode.
145 Disable the read prompt in interactive mode.
147 -S scale --scale=scale
149 Sets the builtin variable scale to the given value assuming that the given
150 value is in base 10. It is a fatal error if the given value is not a valid
155 Print version and copyright and exit.
157 -x --extended-register
159 Enable extended register mode.
163 Enable leading zeroes on numbers greater than -1 and less than 1.
165 Environment variables:
169 Command-line arguments to use on every run.
173 If an integer, the number of characters to print on a line before
174 wrapping. Using 0 will disable line length checking.
178 If an integer and non-zero, reset on SIGINT, rather than exit, when in
181 If zero, do not reset on SIGINT in all cases, but exit instead.
183 Overrides the default, which is %s.
187 If an integer and non-zero, enable TTY mode when it is available.
189 If zero, disable TTY mode in all cases.
191 Overrides the default, which is TTY mode %s.
195 If an integer and non-zero, enable prompt when TTY mode is possible.
197 If zero, disable prompt in all cases.
199 Overrides the default, which is prompt %s.
203 If an integer and non-zero, exit when expressions or expression files are
204 given on the command-line, and does not exit when an integer and zero.
206 Overrides the default, which is %s.
210 If an integer and non-zero, clamp digits larger than or equal to the
211 current ibase when parsing numbers.
213 Overrides the default, which is %s.