NKF

Section: User Contributed Perl Documentation (3)
Updated: 2021-01-26
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NAME

NKF - Perl extension for Network Kanji Filter  

SYNOPSIS


  use NKF;
  $output = nkf("-s",$input);  

DESCRIPTION

This is a Perl Extension version of nkf (Network Kanji Filter). It converts the last argument and return converted result. Conversion details are specified by flags before the last argument. Nkf is a yet another kanji code converter among networks, hosts and terminals. It converts input kanji code to designated kanji code such as ISO-2022-JP, Shift_JIS, EUC-JP, UTF-8, UTF-16 or UTF-32.

One of the most unique faculty of nkf is the guess of the input kanji encodings. It currently recognizes ISO-2022-JP, Shift_JIS, EUC-JP, UTF-8, UTF-16 and UTF-32. So users needn't set the input kanji code explicitly.

By default, X0201 kana is converted into X0208 kana. For X0201 kana, SO/SI, SSO and ESC-(-I methods are supported. For automatic code detection, nkf assumes no X0201 kana in Shift_JIS. To accept X0201 in Shift_JIS, use -X, -x or -S.

multiple options are specifed as seprate strings, such as

  print nkf('--ic=UTF8-MAC', '-w', $string), "\n";

except the last arguments.  

OPTIONS

-J -S -E -W -W16 -W32 -j -s -e -w -w16 -w32
Specify input and output encodings. Upper case is input. cf. --ic and --oc.
-J
ISO-2022-JP (JIS code).
-S
Shift_JIS and JIS X 0201 kana. EUC-JP is recognized as X0201 kana. Without -x flag, JIS X 0201 Katakana (a.k.a.halfwidth kana) is converted into JIS X 0208. If you use Windows, see Windows-31J (CP932).
-E
EUC-JP.
-W
UTF-8N.
-W16[BL][0]
UTF-16. B or L gives whether Big Endian or Little Endian. 0 gives whther put BOM or not.
-W32[BL][0]
UTF-32. B or L gives whether Big Endian or Little Endian. 0 gives whther put BOM or not.
-b -u
Output is buffered (DEFAULT), Output is unbuffered.
-t
No conversion.
-i[@B]
Specify the escape sequence for JIS X 0208.
-i@
Use ESC ( @. (JIS X 0208-1978)
-iB
Use ESC ( B. (JIS X 0208-1983/1990 DEFAULT)
-o[BJ]
Specify the escape sequence for US-ASCII/JIS X 0201 Roman. (DEFAULT B)
-r
{de/en}crypt ROT13/47
-h[123] --hiragana --katakana --katakana-hiragana
-h1 --hiragana
Katakana to Hiragana conversion.
-h2 --katakana
Hiragana to Katakana conversion.
-h3 --katakana-hiragana
Katakana to Hiragana and Hiragana to Katakana conversion.
-T
Text mode output (MS-DOS)
-f[m [- n]]
Folding on m length with n margin in a line. Without this option, fold length is 60 and fold margin is 10.
-F
New line preserving line folding.
-Z[0-3]
Convert X0208 alphabet (Fullwidth Alphabets) to ASCII.
-Z -Z0
Convert X0208 alphabet to ASCII.
-Z1
Convert X0208 kankaku to single ASCII space.
-Z2
Convert X0208 kankaku to double ASCII spaces.
-Z3
Replacing fullwidth >, <, ", & into '&gt;', '&lt;', '&quot;', '&amp;' as in HTML.
-X -x
With -X or without this option, X0201 is converted into X0208 Kana. With -x, try to preserve X0208 kana and do not convert X0201 kana to X0208. In JIS output, ESC-(-I is used. In EUC output, SS2 is used.
-B[0-2]
Assume broken JIS-Kanji input, which lost ESC. Useful when your site is using old B-News Nihongo patch.
-B1
allows any chars after ESC-( or ESC-$.
-B2
force ASCII after NL.
-I
Replacing non iso-2022-jp char into a geta character (substitute character in Japanese).
-m[BQN0]
MIME ISO-2022-JP/ISO8859-1 decode. (DEFAULT) To see ISO8859-1 (Latin-1) -l is necessary.
-mB
Decode MIME base64 encoded stream. Remove header or other part before conversion.
-mQ
Decode MIME quoted stream. '_' in quoted stream is converted to space.
-mN
Non-strict decoding. It allows line break in the middle of the base64 encoding.
-m0
No MIME decode.
-M
MIME encode. Header style. All ASCII code and control characters are intact.
-MB
MIME encode Base64 stream. Kanji conversion is performed before encoding, so this cannot be used as a picture encoder.
-MQ
Perform quoted encoding.
-l
Input and output code is ISO8859-1 (Latin-1) and ISO-2022-JP. -s, -e and -x are not compatible with this option.
-L[uwm] -d -c
Convert line breaks.
-Lu -d
unix (LF)
-Lw -c
windows (CRLF)
-Lm
mac (CR)

Without this option, nkf doesn't convert line breaks.

--fj --unix --mac --msdos --windows
Convert for these systems.
--jis --euc --sjis --mime --base64
Convert to named code.
--jis-input --euc-input --sjis-input --mime-input --base64-input
Assume input system
--ic=input codeset --oc=output codeset
Set the input or output codeset. NKF supports following codesets and those codeset names are case insensitive.
ISO-2022-JP
a.k.a. RFC1468, 7bit JIS, JUNET
EUC-JP (eucJP-nkf)
a.k.a. AT&T JIS, Japanese EUC, UJIS
eucJP-ascii
eucJP-ms
CP51932
Microsoft Version of EUC-JP.
Shift_JIS
a.k.a. SJIS, MS_Kanji
Windows-31J
a.k.a. CP932
UTF-8
same as UTF-8N
UTF-8N
UTF-8 without BOM
UTF-8-BOM
UTF-8 with BOM
UTF8-MAC (input only)
decomposed UTF-8
UTF-16
same as UTF-16BE
UTF-16BE
UTF-16 Big Endian without BOM
UTF-16BE-BOM
UTF-16 Big Endian with BOM
UTF-16LE
UTF-16 Little Endian without BOM
UTF-16LE-BOM
UTF-16 Little Endian with BOM
UTF-32
same as UTF-32BE
UTF-32BE
UTF-32 Big Endian without BOM
UTF-32BE-BOM
UTF-32 Big Endian with BOM
UTF-32LE
UTF-32 Little Endian without BOM
UTF-32LE-BOM
UTF-32 Little Endian with BOM
--fb-{skip, html, xml, perl, java, subchar}
Specify the way that nkf handles unassigned characters. Without this option, --fb-skip is assumed.
--prefix=escape charactertarget character..
When nkf converts to Shift_JIS, nkf adds a specified escape character to specified 2nd byte of Shift_JIS characters. 1st byte of argument is the escape character and following bytes are target characters.
--no-cp932ext
Handle the characters extended in CP932 as unassigned characters.
--no-best-fit-chars
When Unicode to Encoded byte conversion, don't convert characters which is not round trip safe. When Unicode to Unicode conversion, with this and -x option, nkf can be used as UTF converter. (In other words, without this and -x option, nkf doesn't save some characters)

When nkf converts strings that related to path, you should use this opion.

--cap-input
Decode hex encoded characters.
--url-input
Unescape percent escaped characters.
--numchar-input
Decode character reference, such as ``&#....;''.
--
Ignore rest of -option.
 

AUTHOR

Copyright (c) 1987, Fujitsu LTD. (Itaru ICHIKAWA).

Copyright (c) 1996-2015, The nkf Project.  

SEE ALSO

perl(1). nkf(1)


 

Index

NAME
SYNOPSIS
DESCRIPTION
OPTIONS
AUTHOR
SEE ALSO