bcal - Man Page

bcal [-b [expr]] [-c N] [-p N] [-f loc] [-s bytes] [expr] [N [unit]] [-m] [-d] [-h]

bcal (Byte CALculator) is a command-line utility to help with numerical calculations and expressions involving binary prefixes, SI/IEC conversion, byte addressing, base conversion, LBA/CHS calculation etc.

It includes a built-in expression mode (-b) for general-purpose numerical calculations.

bcal uses [SI and IEC binary prefixes]: https://en.wikipedia.org/wiki/Binary_prefix

 * evaluate arithmetic expressions involving storage units
 * perform general purpose calculations (built-in expression mode)
   - arithmetic: addition, subtraction, multiplication, division, modulo
   - bitwise: AND (&), OR (|), XOR (^), complement (~), lshift (<<), rshift (>>)
   - functions: exp(n), log(base, n), ln(n) [natural log], pow(n, exponent), root(radical, n)
 * works with piped input or file redirection
 * convert to IEC/SI standard data storage units
 * interactive mode with the last valid result stored for reuse
 * show the address in bytes
 * show address as LBA:OFFSET
 * convert CHS to LBA and vice versa
 * base conversion to binary, decimal and hex
 * show bit positions with bit value of a number
 * custom sector size, max heads/cylinder and max sectors/track
 * minimal dependencies

1. Interactive mode: bcal enters the REPL mode if no arguments are provided. Storage unit conversion, base conversion and expression evaluation are supported in this mode. The last valid result is stored in the variable r.
2. Expression: Expression passed as argument in one-shot mode must be within double quotes. Inner spaces are ignored. Supported operators: +, -, *, /, % and C bitwise operators (except ~ due to storage width dependency).
3. N [unit]: N can be a decimal or '0x' prefixed hex value. unit can be B/KiB/MiB/GiB/TiB/kB/MB/GB/TB. Default is Byte. As all of these tokens are unique, unit is case-insensitive.
4. Numeric representation: Decimal and hex are recognized in expressions and unit conversions. Binary is also recognized in other operations.
5. Syntax: Prefix hex inputs with '0x', binary inputs with '0b'.
6. Precision: 128 bits if __uint128_t is available or 64 bits for numerical conversions. Floating point operations use long double. Negative values in storage expressions are unsupported. Only 64-bit operating systems are supported.
7. Fractional bytes do not exist, because they can't be addressed. bcal shows the floor value of non-integer bytes.
8. CHS and LBA syntax:
    - LBA: 'lLBA-MAX_HEAD-MAX_SECTOR'   [NOTE: LBA starts with 'l' (case ignored)]
    - CHS: 'cC-H-S-MAX_HEAD-MAX_SECTOR' [NOTE: CHS starts with 'c' (case ignored)]
    - Format conversion arguments must be hyphen separated.
    - Any unspecified value, including the one preceding the first '-' to the one following the last '-', is considered '0' (zero).
    - Examples:
      - 'c-50--0x12-' -> C = 0, H = 50, S = 0, MH = 0x12, MS = 0
      - 'l50-0x12' -> LBA = 50, MH = 0x12, MS = 0
9. Default values:
    - sector size: 0x200 (512)
    - max heads per cylinder: 0x10 (16)
    - max sectors per track: 0x3f (63)
10. Expression mode: r is synced and can be used in expressions. The built-in evaluator uses long double arithmetic.

-b=[expr]

Start in numeric expression mode. If expression is provided, evaluate and quit.

-c=N

Show decimal, binary and hex representation of positive integer N.

-p=N

Show bit position (reversed if set) and bit value of a number.

-f=loc

Convert CHS to LBA or LBA to CHS. loc is hyphen-separated representation of LBA or CHS. Please refer to the Operational Notes section for more details.

-s=bytes

Sector size in bytes. Default value is 512.

-m

Show minimal output (e.g. decimal bytes).

-d

Enable debug information and logs.

-h

Show program help, storage sizes on the system and exit.

b

Toggle numeric expression mode.

r

Show result from last operation.

s

Show sizes of storage types.

?

Show prompt help.

q, double Enter

Quit the program.

1. Evaluate arithmetic expression of storage units

   $ bcal "(5kb+2mb)/3"
   $ bcal "5 tb / 12"
   $ bcal "2.5mb*3"
   $ bcal "(2giB * 2) / (2kib >> 2)"

2. Convert storage capacity to other units and get address, LBA.

   $ bcal 20140115 b
   $ bcal 0x1335053 B
   $ bcal 0xaabbcc kb
   $ bcal 0xdef Gib
   Note that the units are case-insensitive.

3. Convert storage capacity, set sector size to 4096 to calculate LBA.

   $ bcal 0xaabbcc kb -s 4096

4. Convert LBA to CHS.

   $ bcal -f l500
   $ bcal -f l0x600-18-0x7e
   $ bcal -f l0x300-0x12-0x7e

5. Convert CHS to LBA.

   $ bcal -f c10-10-10
   $ bcal -f c0x10-0x10-0x10
   $ bcal -f c0x10-10-2-0x12
   $ bcal -f c-10-2-0x12
   $ bcal -f c0x10-10--0x12

6. Show binary, decimal and hex representations of a number.

   $ bcal -c 20140115
   $ bcal -c 0b1001100110101000001010011
   $ bcal -c 0x1335053
   bcal> c 20140115 // Interactive mode

7. Perform bitwise operations.

   $ bcal -b '0xFF & 0x0F'
   $ bcal -b '0x0F | 0xF0'
   $ bcal -b '0xFF ^ 0xF0'
   $ bcal -b '~0xF0'
   $ bcal -b '0x01 << 3'
   $ bcal -b '0x10 >> 2'
   $ bcal -b '(0xFF & 0x0F) | (0x0F << 4)'

8. Use expression mode.

   $ bcal -b '3.5 * 2.1 + 5.7'
   bcal> b // Interactive mode
   expr> 3.5 * 2.1 + 5.7

9. Pipe input.

   $ printf '15 kib + 15 gib \n r / 5' | bcal -m
   $ printf '15 + 15 + 2' | bcal -bm

10. Redirect from file.

    $ cat expr
    15 gib + 15 kib
    r / 5
    $ bcal -m < expr

11. Use as a general-purpose calculator.

    $ bcal -b

12. Use mathematical functions.

    $ bcal -b 'root(2, 17.3)' // square root on 17.3
    $ bcal -b 'exp(5.2)'
    $ bcal -b 'pow(2, 8)'
    $ bcal -b 'pow(10, 3) + root(2, 9)'

Arun Prakash Jana <engineerarun@gmail.com>

https://github.com/jarun/bcal

https://github.com/jarun/bcal/issues

Copyright © 2016 Arun Prakash Jana <engineerarun@gmail.com>

License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.