We will see how to use the bc tool (Basic Calculator) in this post.

BC tool

bc is a standard utiilty in most of the *nix Operating Systems. It stands for Basic Calculator.

Invoke the utility

Just type bc in the terminal/shell to bring up the calculator.

raghs@Raghs-LegionY540-TPIN:/mnt/c/WINDOWS/System32$ bc
bc 1.07.1
Copyright 1991-1994, 1997, 1998, 2000, 2004, 2006, 2008, 2012-2017 Free Software Foundation, Inc.
This is free software with ABSOLUTELY NO WARRANTY.
For details type `warranty'.

The utility waits for your input without prompt, unlike other interpreters. You can directly type your inputs.

Usage

We can type the numbers and the operators like what we do in the typical calculator, for the bc utility to calculate the result of the expression and print it in the next line.

Example: If you simply type a number and press the Enter key, the bc tool will return the same number.

1
1

Example 2: Do a simple math.

1 + 1 
2

Nothing special here. The expression was evaluated and the result was printed on the next line.

The spaces around the operator is just for the convenience of the human readers, and it does not have make any difference.

Caution

Please be aware of the fact it is a basic calculator, and hence the operands should NOT ne specified with any separators, in such case, it will throw an error.

raghs@Raghs-LegionY540-TPIN:~$ bc
bc 1.07.1
Copyright 1991-1994, 1997, 1998, 2000, 2004, 2006, 2008, 2012-2017 Free Software Foundation, Inc.
This is free software with ABSOLUTELY NO WARRANTY.
For details type `warranty'.
1 + 1
2
last + 1000
1002
last + 1,000
(standard_in) 3: syntax error

From the above example, it is clearly evident that the 2nd expression works well when the 2nd operand is specified without any separator (1000), whereas the 3rd expression failed as the operand was supplied with a separator (1,000).

Exit from the tool

To exit from the bc tool, you simply type the quit and press Enter key to come out of the tool in the terminal.

1 + 1
2
quit
raghs@Raghs-LegionY540-TPIN:/mnt/c/WINDOWS/System32$

You can press Ctrl+C similar to other tools but this bc tool will prompt with you the right hint to use quit.

raghs@Raghs-LegionY540-TPIN:~$ bc
bc 1.07.1
Copyright 1991-1994, 1997, 1998, 2000, 2004, 2006, 2008, 2012-2017 Free Software Foundation, Inc.
This is free software with ABSOLUTELY NO WARRANTY.
For details type `warranty'.
^C
(interrupt) use quit to exit.
quit
raghs@Raghs-LegionY540-TPIN:~$

References

GNU Reference

Cheers,
RM…
Raghavan alias Saravanan Muthu
29 Sep 2021 | Wed | 23:20:37 PM IST

How to Use the BC Tool