[鸟哥笔记]简单好用的计算器bc

-bash-3.2$ man bc
bc(1)                                                                    bc(1)

NAME
       bc - An arbitrary precision calculator language

SYNTAX
       bc [ -hlwsqv ] [long-options] [  file ... ]

VERSION
       This man page documents GNU bc version 1.06.

DESCRIPTION
       bc is a language that supports arbitrary precision numbers with interactive execution of statements.  There are some similarities
       in the syntax to the C programming language.  A standard math library is available by command line  option.   If  requested,  the
       math  library is defined before processing any files.  bc starts by processing code from all the files listed on the command line
       in the order listed.  After all files have been processed, bc reads from the standard input.  All code is executed as it is read.
       (If a file contains a command to halt the processor, bc will never read from the standard input.)

       This  version of bc contains several extensions beyond traditional bc implementations and the POSIX draft standard.  Command line
       options can cause these extensions to print a warning or to be rejected.  This document describes the language accepted  by  this
       processor.  Extensions will be identified as such.

   OPTIONS
       -h, --help
              Print the usage and exit.

       -i, --interactive
              Force interactive mode.

       -l, --mathlib
              Define the standard math library.

       -w, --warn
              Give warnings for extensions to POSIX bc.

       -s, --standard
              Process exactly the POSIX bc language.

       -q, --quiet
              Do not print the normal GNU bc welcome.

       -v, --version
              Print the version number and copyright and quit.