blocks|key|814707|text|如果将C与java进行比较，C更接近硬件，因为java不直接在系统上运行。Java在java+virtual+machine上执行，然后在系统上运行。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|814708|C在它和系统之间没有这样的一层，因此更接近硬件。|814709|entityMap|0|LINK|mutability|MUTABLE|url|http://de.wikipedia.org/wiki/Java_Virtual_Machine^0|3|1|5|4|16|K|0|0|0^^$0|@$1|2|3|4|5|6|7|P|8|@$9|Q|A|R|B|C]|$9|S|A|T|B|C]]|D|@$9|U|A|V|1|W]]|E|$]]|$1|F|3|G|5|6|7|X|8|@]|D|@]|E|$]]|$1|H|3|-4|5|6|7|Y|8|@]|D|@]|E|$]]]|I|$J|$5|K|L|M|E|$N|O]]]]

If you compare <code>C</code> with <code>java</code>, C is closer to the hardware, because java does not directly operate on the system. Java is executed on the <a href="http://de.wikipedia.org/wiki/Java_Virtual_Machine" rel="nofollow">java virtual machine</a>, which then operates on the system. 

C does not have such a layer between it and the system and is therefore closer to the harware.

blocks|key|4222065|text|它不提供抽象概念来保护您不受硬件和平台细节的影响，例如内存布局和系统API。因此，在你的代码和硬件之间有更少的代码，这就是“更接近硬件”。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4222066|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

It does not provide abstractions to protect you from the specifics of the hardware and platform, such as memory layout and system APIs. Thus is it "closer to the hardware" in the sense that there is less code between your code and the hardware.

blocks|key|4222130|text|没有解释C可执行代码的虚拟机。它被编译成特定于特定CPU的机器指令，这些指令链接在一起并在您的硬件上运行。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4222131|另一个原因是语言本身的设计。当Kernighan和Ritchie为DEC硬件开发C语言时，他们非常注意实际的硬件功能，如寄存器、位移位等。在他们的思维和他们为其编写语言的机器之间没有抽象层。|4222132|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|F|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|G|8|@]|9|@]|A|$]]|$1|D|3|-4|5|6|7|H|8|@]|9|@]|A|$]]]|E|$]]

There's no virtual machine interpreting C executable code. It's compiled into machine instructions, specific to a particular CPU, that are linked together and run on your hardware.

Another reason is the design of the language itself. When Kernighan and Ritchie were developing C for DEC hardware, they were very mindful of actual hardware features like registers, bit shifting, etc. There wasn't a layer of abstraction between their thinking and the machine for which they were writing the language.

blocks|key|820987|text|一个definitive+answer|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|820988|AlgolBCPL语言、BCPL语言和C语言都完全符合以|820989|和Algol+60为代表的传统过程家族...它们是“接近机器的”，因为它们引入的抽象很容易建立在传统计算机提供的具体数据类型和操作的基础上，并且它们依赖于库例程来进行输入输出和与操作系统的其他交互。不太成功的是，他们还使用库过程来指定有趣的控制构造，如协程和过程闭包。同时，它们的抽象层足够高，只要小心，就可以实现机器之间的可移植性。|blockquote|style|BOLD|820990|820991|举个具体的例子，一个C+int很可能映射到一个本机字大小的对象(16位、32位、64位或128位)，对该int对象的操作将使用本机操作码(ADD、MUL等)来执行。|CODE|820992|这与Lisp或Haskell等使用任意精度算术的语言形成对比；这些语言中的整数通常由数字数组表示，并且对它们的操作几乎完全在软件中执行。|820993|在这方面，C是“接近硬件的”，因为它利用了整数运算的本机基础设施。|820994|在所有条件相同的情况下，整数运算在C中将会快得多，因为它利用了本机硬件，但它不能表示或操作任意大的值。|820995|entityMap|0|LINK|mutability|MUTABLE|url|http://cm.bell-labs.com/who/dmr/chist.html^0|2|H|0|0|0|M|V|0|0|C|3|1G|3|0|0|0|0^^$0|@$1|2|3|4|5|6|7|12|8|@]|9|@$A|13|B|14|1|15]]|C|$]]|$1|D|3|E|5|6|7|16|8|@]|9|@]|C|$]]|$1|F|3|G|5|H|7|17|8|@$A|18|B|19|I|J]]|9|@]|C|$]]|$1|K|3|-4|5|6|7|1A|8|@]|9|@]|C|$]]|$1|L|3|M|5|6|7|1B|8|@$A|1C|B|1D|I|N]|$A|1E|B|1F|I|N]]|9|@]|C|$]]|$1|O|3|P|5|6|7|1G|8|@]|9|@]|C|$]]|$1|Q|3|R|5|6|7|1H|8|@]|9|@]|C|$]]|$1|S|3|T|5|6|7|1I|8|@]|9|@]|C|$]]|$1|U|3|-4|5|6|7|1J|8|@]|9|@]|C|$]]]|V|$W|$5|X|Y|Z|C|$10|11]]]]

A <a href="http://cm.bell-labs.com/who/dmr/chist.html" rel="nofollow">definitive answer</a>:

<blockquote>
BCPL, B, and C all fit firmly in the traditional procedural family typified by Fortran and Algol 60...They are `close to the machine' in that the abstractions they introduce are readily grounded in the concrete data types and operations supplied by conventional computers, and they rely on library routines for input-output and other interactions with an operating system. With less success, they also use library procedures to specify interesting control constructs such as coroutines and procedure closures. At the same time, their abstractions lie at a sufficiently high level that, with care, portability between machines can be achieved.</blockquote>

For a specific example, a C <code>int</code> will most likely map to an object of the native word size (16-, 32-, 64-, or 128-bit), and operations on that <code>int</code> object will be performed using native opcodes (ADD, MUL, etc.). 

Contrast that with languages like Lisp or Haskell that use arbitrary-precision arithmetic; integers in those languages are often represented by arrays of digits, and operations on them are performed almost exclusively in software. 

In this respect, C is "close to the hardware" in that it's taking advantage of the native infrastructure for integer operations. 

All things being equal, integer arithmetic in C will be a lot faster since it's taking advantage of the native hardware, but it cannot represent or operate on arbitrarily large values.

One of the advantages of C is that it is closer to the hardware. 
But I do not understand what does it really mean. It would be great help if someone could elaborate.

Why is C closer to the hardware?

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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C语言的一个优点是它更接近硬件。但我不明白这到底是什么意思。如果有人能详细说明，那将是很大的帮助。

问为什么C更接近硬件？
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问为什么C更接近硬件？EN