1BCAL(1) User Commands BCAL(1)
2
6 bcal - Storage expression calculator.
7
9 bcal [-c N] [-f loc] [-s bytes] [expr] [N [unit]] [-b [expr]] [-m] [-d]
10 [-h]
11
13 bcal (Byte CALculator) is a command-line utility to help with numerical
14 calculations and expressions involving data storage units, addressing,
15 base conversion etc.
16 It invokes GNU bc for non-storage expressions. Alternatively, it can
18 also invoke calc (http://www.isthe.com/chongo/tech/comp/calc/) which
19 works better with expressions involving multiple bases. To use calc:
20 export BCAL_USE_CALC=1
22 bcal follows Ubuntu's standard unit conversion and notation policy:
24 https://wiki.ubuntu.com/UnitsPolicy
25
27 * evaluate arithmetic expressions involving storage units
28 * perform general purpose calculations (using bc or calc)
29 * convert to IEC/SI standard data storage units
30 * interactive mode with the last valid result stored for reuse
31 * show the address in bytes
32 * show address as LBA:OFFSET
33 * convert CHS to LBA and vice versa
34 * base conversion to binary, decimal and hex
35 * custom sector size, max heads/cylinder and max sectors/track
36 * minimal dependencies
37
39 1. Interactive mode: bcal enters the REPL mode if no arguments are
40 provided. Storage unit conversion, base conversion and expression
41 evaluation are supported in this mode. The last valid result is
42 stored in the variable r.
43 2. Expression: Expression passed as argument in one-shot mode must be
45 within double quotes. Inner spaces are ignored. Supported opera‐
46 tors: +, -, *, /, % and C bitwise operators (except ~ due to stor‐
47 age width dependency).
48 3. N [unit]: N can be a decimal or '0x' prefixed hex value. unit can
50 be B/KiB/MiB/GiB/TiB/kB/MB/GB/TB following Ubuntu policy. Default
51 is byte. As all of these tokens are unique, unit is case-insensi‐
52 tive.
53 4. Numeric representation: Decimal and hex are recognized in expres‐
55 sions and unit conversions. Binary is also recognized in other
56 operations.
57 5. Syntax: Prefix hex inputs with '0x', binary inputs with '0b'.
59 6. Precision: 128 bits if __uint128_t is available or 64 bits for
61 numerical conversions. Floating point operations use long double.
62 Negative values in storage expressions are unsupported. Only 64-bit
63 operating systems are supported.
64 7. Fractional bytes do not exist, because they can't be addressed.
66 bcal shows the floor value of non-integer bytes.
67 8. CHS and LBA syntax:
69 - LBA: 'lLBA-MAX_HEAD-MAX_SECTOR' [NOTE: LBA starts with 'l'
70 (case ignored)]
71 - CHS: 'cC-H-S-MAX_HEAD-MAX_SECTOR' [NOTE: CHS starts with 'c'
72 (case ignored)]
73 - Format conversion arguments must be hyphen separated.
74 - Any unspecified value, including the one preceding the first
75 '-' to the one following the last '-', is considered '0' (zero).
76 - Examples:
77 - 'c-50--0x12-' -> C = 0, H = 50, S = 0, MH = 0x12, MS = 0
78 - 'l50-0x12' -> LBA = 50, MH = 0x12, MS = 0
79 9. Default values:
81 - sector size: 0x200 (512)
82 - max heads per cylinder: 0x10 (16)
83 - max sectors per track: 0x3f (63)
84 10. bc variables: scale = 10, ibase = 10. r is synced and can be used
86 in expressions. bc is not called in minimal output mode. To use
87 calc instead of bc, export BCAL_USE_CALC=1.
88
90 -c=N Show decimal, binary and hex representation of positive integer
91 N.
92 -f=loc Convert CHS to LBA or LBA to CHS. loc is hyphen-separated repre‐
94 sentation of LBA or CHS. Please refer to the Operational Notes
95 section for more details.
96 -s=bytes
98 Sector size in bytes. Default value is 512.
99 -b=[expr]
101 Start in bc mode. If expression is provided, evaluate in bc and
102 quit.
103 -m Show minimal output (e.g. decimal bytes).
105 -d Enable debug information and logs.
107 -h Show program help, storage sizes on the system and exit.
109
111 b Toggle bc mode.
112 r Show result from last operation.
114 s Show sizes of storage types.
116 ? Show prompt help.
118 q, double Enter
120 Quit the program.
121
123 1. Evaluate arithmetic expression of storage units
124 $ bcal "(5kb+2mb)/3"
126 $ bcal "5 tb / 12"
127 $ bcal "2.5mb*3"
128 $ bcal "(2giB * 2) / (2kib >> 2)"
129 2. Convert storage capacity to other units and get address, LBA.
131 $ bcal 20140115 b
133 $ bcal 0x1335053 B
134 $ bcal 0xaabbcc kb
135 $ bcal 0xdef Gib
136 Note that the units are case-insensitive.
137 3. Convert storage capacity, set sector size to 4096 to calculate LBA.
139 $ bcal 0xaabbcc kb -s 4096
141 4. Convert LBA to CHS.
143 $ bcal -f l500
145 $ bcal -f l0x600-18-0x7e
146 $ bcal -f l0x300-0x12-0x7e
147 5. Convert CHS to LBA.
149 $ bcal -f c10-10-10
151 $ bcal -f c0x10-0x10-0x10
152 $ bcal -f c0x10-10-2-0x12
153 $ bcal -f c-10-2-0x12
154 $ bcal -f c0x10-10--0x12
155 6. Show binary, decimal and hex representations of a number.
157 $ bcal -c 20140115
159 $ bcal -c 0b1001100110101000001010011
160 $ bcal -c 0x1335053
161 bcal> c 20140115 // Interactive mode
162 7. Invoke bc.
164 $ bcal -b '3.5 * 2.1 + 5.7'
166 bcal> b // Interactive mode
167 bc vars: scale = 10, ibase = 10, last = r
168 bc> 3.5 * 2.1 + 5.7
169
171 Arun Prakash Jana <engineerarun@gmail.com>
172
174 https://github.com/jarun/bcal
175
177 https://github.com/jarun/bcal/issues
178
180 Copyright © 2016 Arun Prakash Jana <engineerarun@gmail.com>
181 License GPLv3+: GNU GPL version 3 or later
183 <http://gnu.org/licenses/gpl.html>.
184 This is free software: you are free to change and redistribute it.
185 There is NO WARRANTY, to the extent permitted by law.
186Version 2.2 07 Jan 2020 BCAL(1)