November 2016
Beginner to intermediate
816 pages
19h 58m
Japanese
Content preview from Cクイックリファレンス 第2版
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
17.3
文字分類と変換
317
するかどうかも実装が決める。さらに、式
math_errhandling & MATH_ERREXCEPT
が真なら、
アンダーフローが例外
FE_UNDERFLOW
を起こすかどうかも実装が決める。
17.3
文字分類と変換
標準ライブラリは文字の分類と変換を行うために多数の関数を提供する。ヘッダctype.h
は文字コードが 0から255のバイト文字用の関数を宣言する。ヘッダwctype.hは型
wchar_t
のワイド文字用の関数を宣言する。これらの関数は普通マクロとして実装される。
これらの関数の結果は
isdigit()
と
isxdigit()
を除いて、ロケールカテゴリ
LC_CTYPE
の
現在のロケール設定に依存する。関数
setlocale()
を使ってロケールのクエリや変更がで
きる。
17.3.1
文字分類
表17-12に挙げた関数は文字が指定カテゴリに属するかどうかをテストする。引数がカテ
ゴリ
内の文字コードなら戻り値は非ゼロ値、すなわち
true
となる。
表17-12 文字分類関数
カテゴリ ctype.hの関数 wctype.hの関数
英文字
isalpha() iswalpha()
小文字
islower() iswlower()
大文字
isupper() iswupper()
10進数字
isdigit() iswdigit()
16進数字
isxdigit() iswxdigit()
英数字
isalnum() iswalnum()
表示可能文字（空白を含む）
isprint() iswprint() ...
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.