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diff --git a/man7/units.7 b/man7/units.7 deleted file mode 100644 index e2dd69fe7..000000000 --- a/man7/units.7 +++ /dev/null @@ -1,108 +0,0 @@ -'\" t -.\" Copyright (C) 2001 Andries Brouwer <aeb@cwi.nl> -.\" -.\" SPDX-License-Identifier: Linux-man-pages-copyleft -.\" -.TH units 7 (date) "Linux man-pages (unreleased)" -.SH NAME -units \- decimal and binary prefixes -.SH DESCRIPTION -.SS Decimal prefixes -The SI system of units uses prefixes that indicate powers of ten. -A kilometer is 1000 meter, and a megawatt is 1000000 watt. -Below the standard prefixes. -.RS -.TS -l l l. -Prefix Name Value -q quecto 10\[ha]\-30 = 0.000000000000000000000000000001 -r ronto 10\[ha]\-27 = 0.000000000000000000000000001 -y yocto 10\[ha]\-24 = 0.000000000000000000000001 -z zepto 10\[ha]\-21 = 0.000000000000000000001 -a atto 10\[ha]\-18 = 0.000000000000000001 -f femto 10\[ha]\-15 = 0.000000000000001 -p pico 10\[ha]\-12 = 0.000000000001 -n nano 10\[ha]\-9 = 0.000000001 -\[mc] micro 10\[ha]\-6 = 0.000001 -m milli 10\[ha]\-3 = 0.001 -c centi 10\[ha]\-2 = 0.01 -d deci 10\[ha]\-1 = 0.1 -da deka 10\[ha] 1 = 10 -h hecto 10\[ha] 2 = 100 -k kilo 10\[ha] 3 = 1000 -M mega 10\[ha] 6 = 1000000 -G giga 10\[ha] 9 = 1000000000 -T tera 10\[ha]12 = 1000000000000 -P peta 10\[ha]15 = 1000000000000000 -E exa 10\[ha]18 = 1000000000000000000 -Z zetta 10\[ha]21 = 1000000000000000000000 -Y yotta 10\[ha]24 = 1000000000000000000000000 -R ronna 10\[ha]27 = 1000000000000000000000000000 -Q quetta 10\[ha]30 = 1000000000000000000000000000000 -.TE -.RE -.PP -The symbol for micro is the Greek letter mu, often written u -in an ASCII context where this Greek letter is not available. -.SS Binary prefixes -The binary prefixes resemble the decimal ones, -but have an additional \[aq]i\[aq] -(and "Ki" starts with a capital \[aq]K\[aq]). -The names are formed by taking the -first syllable of the names of the decimal prefix with roughly the same -size, followed by "bi" for "binary". -.RS -.TS -l l l. -Prefix Name Value -Ki kibi 2\[ha]10 = 1024 -Mi mebi 2\[ha]20 = 1048576 -Gi gibi 2\[ha]30 = 1073741824 -Ti tebi 2\[ha]40 = 1099511627776 -Pi pebi 2\[ha]50 = 1125899906842624 -Ei exbi 2\[ha]60 = 1152921504606846976 -Zi zebi 2\[ha]70 = 1180591620717411303424 -Yi yobi 2\[ha]80 = 1208925819614629174706176 -.TE -.RE -.SS Discussion -Before these binary prefixes were introduced, it was fairly -common to use k=1000 and K=1024, just like b=bit, B=byte. -Unfortunately, the M is capital already, and cannot be -capitalized to indicate binary-ness. -.PP -At first that didn't matter too much, since memory modules -and disks came in sizes that were powers of two, so everyone -knew that in such contexts "kilobyte" and "megabyte" meant -1024 and 1048576 bytes, respectively. -What originally was a -sloppy use of the prefixes "kilo" and "mega" started to become -regarded as the "real true meaning" when computers were involved. -But then disk technology changed, and disk sizes became arbitrary numbers. -After a period of uncertainty all disk manufacturers settled on the -standard, namely k=1000, M=1000\ k, G=1000\ M. -.PP -The situation was messy: in the 14k4 modems, k=1000; in the 1.44\ MB -.\" also common: 14.4k modem -diskettes, M=1024000; and so on. -In 1998 the IEC approved the standard -that defines the binary prefixes given above, enabling people -to be precise and unambiguous. -.PP -Thus, today, MB = 1000000\ B and MiB = 1048576\ B. -.PP -In the free software world programs are slowly -being changed to conform. -When the Linux kernel boots and says -.PP -.in +4n -.EX -hda: 120064896 sectors (61473 MB) w/2048KiB Cache -.EE -.in -.PP -the MB are megabytes and the KiB are kibibytes. -.SH SEE ALSO -.UR https://www.bipm.org/\:documents/\:20126/\:41483022/\:SI\-Brochure\-9.pdf -The International System of Units -.UE . |