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Top Forums Programming Compiler/Runtime uses of sizeof Post 302962439 by GSalisbury on Monday 14th of December 2015 04:49:49 PM
Old 12-14-2015
1. & 2. Yes
Code:
string.h

and
Code:
sys/types.h

have been included.
3. An example a might be char
Code:
a[8]

.
4. An example c might be
Code:
int c = sizeof(a)

.
5. Using gcc on RedHat Linux boxes.

What I was after is what, if any, would be the virtue of using:
Code:
c = sizeof(a); strncpy( a, b, c );

vs.
Code:
strncpy( a, b, sizeof(a) );

I'm not a C maven (I can kludge along given good consult) but it seems to me that using the sizeof value in a separate int adds overhead while not altering the execution result.

I appreciate that we're talking fractional nano-seconds and negligible amounts but am interested in clarifying the precept.
 

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Locale::Codes::LangVar(3pm)				 Perl Programmers Reference Guide			       Locale::Codes::LangVar(3pm)

NAME
Locale::Codes::LangVar - standard codes for language variation identification SYNOPSIS
use Locale::Codes::LangVar; $lvar = code2langvar('acm'); # $lvar gets 'Mesopotamian Arabic' $code = langvar2code('Mesopotamian Arabic'); # $code gets 'acm' @codes = all_langvar_codes(); @names = all_langvar_names(); DESCRIPTION
The "Locale::Codes::LangVar" module provides access to standard codes used for identifying language variations, such as those as defined in the IANA language registry. Most of the routines take an optional additional argument which specifies the code set to use. If not specified, the default IANA language registry codes will be used. SUPPORTED CODE SETS
There are several different code sets you can use for identifying language variations. A code set may be specified using either a name, or a constant that is automatically exported by this module. For example, the two are equivalent: $lvar = code2langvar('en','alpha-2'); $lvar = code2langvar('en',LOCALE_CODE_ALPHA_2); The codesets currently supported are: alpha This is the set of alphanumeric codes from the IANA language registry, such as 'arevela' for Eastern Armenian. This code set is identified with the symbol "LOCALE_LANGVAR_ALPHA". This is the default code set. ROUTINES
code2langvar ( CODE [,CODESET] ) langvar2code ( NAME [,CODESET] ) langvar_code2code ( CODE ,CODESET ,CODESET2 ) all_langvar_codes ( [CODESET] ) all_langvar_names ( [CODESET] ) Locale::Codes::LangVar::rename_langvar ( CODE ,NEW_NAME [,CODESET] ) Locale::Codes::LangVar::add_langvar ( CODE ,NAME [,CODESET] ) Locale::Codes::LangVar::delete_langvar ( CODE [,CODESET] ) Locale::Codes::LangVar::add_langvar_alias ( NAME ,NEW_NAME ) Locale::Codes::LangVar::delete_langvar_alias ( NAME ) Locale::Codes::LangVar::rename_langvar_code ( CODE ,NEW_CODE [,CODESET] ) Locale::Codes::LangVar::add_langvar_code_alias ( CODE ,NEW_CODE [,CODESET] ) Locale::Codes::LangVar::delete_langvar_code_alias ( CODE [,CODESET] ) These routines are all documented in the Locale::Codes::API man page. SEE ALSO
Locale::Codes The Locale-Codes distribution. Locale::Codes::API The list of functions supported by this module. http://www.iana.org/assignments/language-subtag-registry The IANA language subtag registry. AUTHOR
See Locale::Codes for full author history. Currently maintained by Sullivan Beck (sbeck@cpan.org). COPYRIGHT
Copyright (c) 2011-2013 Sullivan Beck This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself. perl v5.18.2 2014-01-06 Locale::Codes::LangVar(3pm)
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