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Full Discussion: Can I use wc -l with arithmetic expression?
Top Forums Shell Programming and Scripting Can I use wc -l with arithmetic expression? Post 302131536 by hegemaro on Saturday 11th of August 2007 05:36:07 PM
Old 08-11-2007
You can use sed to strip away the file name. For example, this will sum up the line count for an entire directory and save it as $I.

I=0

for LINES in $(wc -l * | sed -e "s/^ *\([0-9]*\) .*/\1/")
do
(( I += LINES ))
done

echo $I

The tr and cut commands could also be used as in

... for LINE in $(wc -l * | tr -s " " "\t" | cut -f2) ...

But for very large files, the line count could extend to the left-most column and you'd end up cutting the wrong field.

Your example would be written as:

expr $(wc -l filename | sed -e "s/^ *\([0-9]*\) .*$/\1/") / 2
 

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LEARN ABOUT DEBIAN

mdbfontset

mdbFontset(5)							 The m17n Library						     mdbFontset(5)

NAME

       mdbFontset - Fontset

DESCRIPTION

       The m17n library loads a fontset definition from the m17n database by the tags <fontset, FONTSET-NAME>. The plist format of the data is as
       follows:

       FONTSET ::= PER-SCRIPT * PER-CHARSET * FALLBACK *

       PER-SCRIPT ::= '(' SCRIPT PER-LANGUAGE + ')'

       PER-LANGUAGE ::= '(' LANGUAGE FONT-SPEC-ELEMENT + ')'

       PER-CHARSET ::= '(' CHARSET FONT-SPEC-ELEMENT + ')'

       FALLBACK ::= FONT-SPEC-ELEMENT

       FONT-SPEC-ELEMENT ::= '(' FONT-SPEC [ FLT-NAME ] ')'

       FONT-SPEC ::=
	    '(' [ FOUNDRY FAMILY
		  [ WEIGHT [ STYLE [ STRETCH [ ADSTYLE ]]]]]
		REGISTRY
	     [ OTF-SPEC ] [ LANG-SPEC ] ')'

       SCRIPT is a symbol of script name (e.g. latin, han) or nil. LANGUAGE is a two-letter symbol of language name code defined by ISO 639 (e.g.
       ja, zh) or nil.

       FONT-SPEC is to specify properties of a font. FOUNDRY to REGISTRY are symbols corresponding to Mfoundry to Mregistry property of a font.
       See m17nFont for the meaning of each property.

       OTF-SPEC is a symbol specifyng the required OTF features. The symbol name has the following syntax.

	 OTF-SPEC-NAME ::= ':otf=' SCRIPT LANGSYS ? GSUB-FEATURES ? GPOS-FEATURES ?

	 SCRIPT ::= SYMBOL
	 LANGSYS ::= '/' SYMBOL

	 GSUB-FEATURES ::= '=' FEATURE-LIST ?

	 GPOS-FEATURES ::= '+' FEATURE-LIST ?

	 FEATURE-LIST ::= '~' ? FEATURE ( ',' '~' ? FEATURE ',' )

       Here, FEATURE is a four-letter Open Type feature.

       LANG-SPEC is a symbol specifying the required language support. The symbol name has the following syntax.

	 LANG-SPEC-NAME ::= ':lang=' LANG

       Here, LANG is a two or three-letter ISO-639 language code.

       FLT-NAME is a name of Font Layout Table (Font Layout Table).

EXAMPLE

       This is an example of PER_SCRIPT.

       (han
	 (ja
	   ((jisx0208.1983-0)))
	 (zh
	   ((gb2312.1980-0)))
	 (nil
	   ((big5-0))))

       It instructs the font selector to use a font of registry 'jisx0208.1983-0' for a 'han' character (i.e. a character whose Mscript property
       is 'han') if the character has Mlanguage text property 'ja' in an M-text and the character is in the repertories of such fonts. Otherwise,
       try a font of registry 'gb2312.1980-0' or 'big5-0'. If that 'han' character does not have Mlanguage text property, try all three fonts.

       See the function mdraw_text() for the detail of how a font is selected.

COPYRIGHT

       Copyright (C) 2001 Information-technology Promotion Agency (IPA)
       Copyright (C) 2001-2011 National Institute of Advanced Industrial Science and Technology (AIST)
       Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License
       <http://www.gnu.org/licenses/fdl.html>.

Version 1.6.2							    12 Jan 2011 						     mdbFontset(5)
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