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.
16.2
境界検査関数
279
ここに述べた条件のいくつかには「抜け穴」がある。名前空間で、あるいは静的リンケー
ジで識別子再利用ができるが、識別子の多重定義は混乱を招くので、標準ヘッダで宣言さ
れた識別子は完全に避けるのが一般には最も安全だ。以後の節では、C標準の将来の拡張
のために予約された識別子も挙げる。上に述べた箇条書きの最後の3規則はそのような予約
識別子にも当てはまる。
16.2
境界検査関数
C標準ライブラリの伝統的な関数の多くは、プログラマがポインタ引数で指定した文字
列を配列にコピーする。これらの関数には、配列が結果を格納する十分な大きさがあるか
どうかを検査する方法がない。プログラマだけが、配列の末端を越えてデータが書かれな
いことを保証する責任を負う。もしデータがあふれてしまうと、メモリの隣接オブジェクト
を変更しかねない。これはプログラムの信頼性と安全性への重大な脅威であり、クラッシュ
の危険がある。
この問題
を回避するために、C11標準附属書K「境界検査インタフェース」は、伝統的な
標準 C関数の代替として安全な新関数を導入した。これらの代替関数は、セキュア関数と
も呼ばれるが、転送先配列のサイズを指定する追加引数をとる。セキュア関数は、この情
報を用いて、生成した結果が配列境界を越えないことを保証する。セキュア関数の名前は、
例えば、
strcpy_s()
のように語尾が
_s
（「セキュア」の
s
）で終わる。従来の関数
strcpy()
と
異なり、
strcpy_s()
は指定された転送先配列が十
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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.