問個土問題,Return _("XXX");的下劃線做何用途

MaxWu

return _("it is based on your username";

這里的下劃線是做什么用的呢?

謝謝.

dreamice

這個是win下面的吧

alexhappy

是不是表示寬字符。。。忘了

MMMIX

原帖由 MaxWu 于 2009-5-11 14:55 發(fā)表
return _("it is based on your username");

這里的下劃線是做什么用的呢?

那就是個宏，具體什么作用要看它的定義

BTW, 單從語法看，也可以是個函數(shù)。不過 _ 通常是個和 gettext 相關(guān)的宏。

[ 本帖最后由 MMMIX 于 2009-5-11 16:49 編輯 ]

MaxWu

補充一下, 是Linux下的, cracklib里面的.
我來查一下是不是Macro.
先謝謝各位.

connet

宏
很多 軟件 用這個來 國際化
gettext

guhan010

windows下肯定沒有的 吧，我從來沒用過。
定義寬字符是用T或者L吧。你這個沒見過。

daybreakcx

是個宏，功能看定義

MaxWu

  對,gettext,下面這個message可以做解釋.

Re: _() Macro
From: Trevor Johnson <trevor jpj net>
To: Andreas Sliwka <goff nef wh uni-dortmund de>
cc: gtk-app-devel-list redhat com
Subject: Re: _() Macro
Date: Sat, 20 Nov 1999 07:26:36 -0500 (EST)
> Hi,

Hi, Andreas.

>   I jsut read the gnome documentation and found in gnomeabout.html the
>   macro _() (it wasnt defined but used). The corresponding text says:
>  >note that the descriptive text is surrounded by the _(). This will have
>  > the text translated to the the user's language at runtime.
>
>  How is this done? Where do I find more information/documentation about this?

If you have GNU gettext, you can read about it on one of the gettext info
pages:

     Many packages use `_' (a simple underline) as a keyword, and write
  `_("Translatable string"' instead of `gettext ("Translatable
  string"'.  Further, the coding rule, from GNU standards, wanting that
  there is a space between the keyword and the opening parenthesis is
  relaxed, in practice, for this particular usage.  So, the textual
  overhead per translatable string is reduced to only three characters:
  the underline and the two parentheses.  However, even if GNU `gettext'
  uses this convention internally, it does not offer it officially.  The
  real, genuine keyword is truly `gettext' indeed.  It is fairly easy for
  those wanting to use `_' instead of `gettext' to declare:

       #include <libintl.h>
       #define _(String) gettext (String)

  instead of merely using `#include <libintl.h>'.

> mfg

Mit freundlichen gruessen.
__
Trevor Johnson