In the
C programming language
''The C Programming Language'' (sometimes termed ''K&R'', after its authors' initials) is a computer programming book written by Brian Kernighan and Dennis Ritchie, the latter of whom originally designed and implemented the language, as well as ...
,
register is a
reserved word
In a computer language, a reserved word (also known as a reserved identifier) is a word that cannot be used as an identifier, such as the name of a variable, function, or label – it is "reserved from use". This is a syntactic definition, and a r ...
(or keyword), type modifier,
storage class, and hint. The
register keyword was deprecated in
C++, until it became reserved and unused in
C++17
C++17 is a version of the ISO/ IEC 14882 standard for the C++ programming language. C++17 replaced the prior version of the C++ standard, called C++14, and was later replaced by C++20.
History
Before the C++ Standards Committee fixed a 3-yea ...
. It ''suggests'' that the
compiler
In computing, a compiler is a computer program that translates computer code written in one programming language (the ''source'' language) into another language (the ''target'' language). The name "compiler" is primarily used for programs that ...
stores a
declared variable in a
CPU
A central processing unit (CPU), also called a central processor, main processor or just processor, is the electronic circuitry that executes instructions comprising a computer program. The CPU performs basic arithmetic, logic, controlling, an ...
register
Register or registration may refer to:
Arts entertainment, and media Music
* Register (music), the relative "height" or range of a note, melody, part, instrument, etc.
* ''Register'', a 2017 album by Travis Miller
* Registration (organ), the ...
(or some other faster location) instead of in
random-access memory
Random-access memory (RAM; ) is a form of computer memory that can be read and changed in any order, typically used to store working data and machine code. A random-access memo