C localization functions: Difference between revisions

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{{useUse dmy dates|date=JanuaryDecember 20122020}}

{{C Standard Library}}

In [[computing]], '''C localization functions''' are a group of functions in the [[C (programming language)|C programming language]] implementing basic localization routines.<ref name="c99">{{cite book | url=http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1124.pdf | title=ISO/IEC 9899:1999 specification | at=p. 204, § 7.11 ''Localization'' }}</ref><ref name="c_primer">{{cite book|title=C primer plus | first=Stephen | last=Prata | year=2004 | publisher=Sams Publishing | isbn=0-672-32696-5 | at=Appendix B, Section V: The Standard ANSI C Library with C99 Additions}}</ref> The functions are used in multilingual programs to adapt to the specific locale. In particular, the way of displaying of numbers and currency can be modified. These settings affect the behaviour of [[C file input/output|input/output functions]] in the C Standard Library.<ref>{{Cite web|url=http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1570.pdf|title=ISO/IEC 9899:201x|date=12 April 2011|page=181|archive-url=https://web.archive.org/web/20180329042731/http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1570.pdf|archive-date=29 March 2018|url-status=}}</ref>

==Overview of functions==

C localization functions and types are defined in <tt>{{mono|locale.h</tt>}} (<tt>{{mono|clocale</tt>}} header in C++).<ref name=www.utas.edu.au>{{cite web|title=locale.h|url=http://www.utas.edu.au/infosys/info/documentation/C/CStdLib.html#locale.h|work=utas.edu.au|publisher=infosys|accessdate=14 September 2011|archive-date=4 June 2012|archive-url=https://web.archive.org/web/20120604201614/http://www.utas.edu.au/infosys/info/documentation/C/CStdLib.html#locale.h|url-status=dead}}</ref><ref>{{Cite web|url=https://github.com/openbsd/src/blob/master/include/locale.h|title=openbsd/src|website=GitHub|language=en|access-date=2018-04-09}}</ref>

{| class="wikitable" style="font-size:0.85em;"

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! Description

|-

! style="font-family:monospace" | {{anchor|setlocale}}<code>[http://en.cppreference.com/w/c/locale/setlocale setlocale]</code>

| sets and gets the current C locale

|-

! style="font-family:monospace" | {{anchor|localeconv}}<code>[http://en.cppreference.com/w/c/locale/localeconv localeconv]</code>

| returns numeric and monetary formatting details of the current locale

|-

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==Criticism==

C standard localization functions are criticized because the localization state is stored globally. This means that in a given program all operations involving a locale can use only one locale at a time. As a result, it is very difficult to implement programs that use more than one locale.<ref>{{cite web | title=The Standard C Locale and the Standard C++ Locales | url=http://www.math.hkbu.edu.hk/parallel/pgi/doc/pgC++_lib/stdlibug/sta_9169.htm | publisher=Rogue Wave Software, Inc. | year=1996 | access-date=10 November 2011 | archive-date=19 February 2020 | archive-url=https://web.archive.org/web/20200219173855/http://www.math.hkbu.edu.hk/parallel/pgi/doc/pgC++_lib/stdlibug/sta_9169.htm | url-status=dead }}</ref>

The functions alter the behavior of printf/scanf/strtod which are often used to write saved data to a file or to other programs. The result is that a saved file in one locale will not be readable in another locale, or not be readable ''at all'' due to assumptions such as "numbers end at comma characters". Most large-scale software forces the locale to "C" (or another fixed value) to work around these problems.

FUNCTIONS

syntax:

(i) return_type name of function()

TYPES OF FUNCTIONS

1.With No arguments and no return type:

⦁ In this type of function ,the function is called without passing any arguments.so the control moves fromcalling function to called function.

⦁ the variables are declared in th function,data is processed in the function and the result is also displayed in the function.Now the control returns from called to calling function.

2.with Arguments and no return type:

In this type of function the function is invoked by passing some arguement

⦁ now the control moves from calling function t the called function with these arguements

⦁ if any variables required,declared in the function

⦁ process the data

⦁ display the result in the function

⦁ the control returns back to its calling function

⦁ Actual parameters:the parameters present in the function call are call actual parameters.

⦁ Formal parameters:The parameters present in the function definition are called Formal parameters

⦁ The actual and formal parameters should be in:

a. in number and data types

3.With Arguments and return type:

⦁ The result is not displayed in the function ,it will send back to the program

⦁ RETURN : By using return statement ,the result is sent back to its calling function

4.Call by reference.

==Example==

<sourcesyntaxhighlight lang="cppc">

#include <stdio.h>

#include <stdlib.h>

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return EXIT_SUCCESS;

}

</syntaxhighlight>

</source>

==See also==

*[[Locale (computer software)]]

==References==

{{Reflist}}

==See also==

*[[Locale]]

{{use dmy dates|date=January 2012}}

[[Category:C standard library]]