C language is a common high-level language, originally
designed by Dennis Ritchie in the Bell Labs for the development of UNIX
operating system. The C language was first implemented in 1972 on the DEC
PDP-11 computer.
In 1978, Brian Kernighan and Dennis Ritchie produced
the first publicly available description of C, now known as the K & R
standard.
UNIX operating system, C compiler, and almost all UNIX
applications are written in C language. For a variety of reasons, the C
language has now become a widely used professional language.
·
Easy to learn.
·
Structured language.
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It produces efficient programs.
·
It can handle the underlying activities.
·
It can be compiled on a variety of computer platforms.
About C
·
The C language was invented for the purpose of writing a UNIX
operating system.
·
C language is based on the B language, B language is probably
introduced in 1970.
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The C language standard was developed in 1988 by the American
National Standards Institute (ANSI).
·
As of 1973, the UNIX operating system was written entirely in C
language.
·
At present, C language is the most widely used system
programming language.
·
Most of the advanced software is implemented using the C
language.
·
Today's most popular Linux operating system and RDBMS
(Relational Database Management System: relational database management system)
MySQL are written in C language.
Why use C?
C language was
originally used for system development work, especially the composition of the
operating system procedures. Since the code generated by the C language
runs almost as fast as the code written in the assembly language, the C
language is used as the system development language. Here are a few
examples of using C:
·
operating system
·
Language compiler
·
Assembler
·
text editor
·
printer
·
Network drive
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Modern procedures
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database
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Language interpreter
·
Physical tools
C program
A C language program,
which can be 3 lines or millions of lines, can be written in one or
more text files with the extension ".c" ,
for example, hello.c . You can use "vi" , "vim" or
any other text editor to write your C program.
This tutorial assumes
that you already know how to edit a text file and how to write the source code
in the program file.
C11
C11 (also known as
C1X) refers to ISO standard ISO / IEC 9899: 2011, is the latest C language
standard. Prior to its C language standard for C99.
New features
·
Alignment normalization
(including the _Alignas notation, the alignof operator, the aligned_alloc
function, and the <stdalign.h> header file).
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_Noreturn function tag, similar
to gcc __attribute __ ((noreturn)).
·
_Generic keywords.
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Multithreading support,
including:
_Thread_local storage type identifier, <threads.h> header file, which contains the thread creation and management functions.
_Atomic type modifier and <stdatomic.h> header file.
_Thread_local storage type identifier, <threads.h> header file, which contains the thread creation and management functions.
_Atomic type modifier and <stdatomic.h> header file.
·
Enhanced Unicode
support. Enhanced Unicode support based on the C Unicode Technical Report
ISO / IEC TR 19769: 2004. Including the char16_t and char32_t data types for
UTF-16 / UTF-32 encoding, providing the header file <uchar.h> containing
the unicode string conversion function.
·
Removed the gets () function,
using a new, more secure function gets_s () instead.
·
Added a border check function
interface that defines new security functions such as fopen_s (), strcat_s (),
and so on.
·
Added more floating point
processing macros (macros).
·
Anonymous structure / consortium
support. This gcc already exists, C11 will be introduced into the
standard.
·
Static assertions, _ Static_assert
(), are processed after interpreting #if and #error.
·
New fopen () mode, ("...
x"). Similar to POSIX in the O_CREAT | O_EXCL, in the file lock is
more commonly used.
·
Added the quick_exit () function
as a third way to terminate the program. You can do the least cleanup when
exit () fails.
History of C Programming Language: Click Here
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