Include directiveMany programming languages and other computer files have a directive, often called include, import, or copy, that causes the contents of the specified file to be inserted into the original file. These included files are called s or copybooks. They are often used to define the physical layout of program data, pieces of procedural code, and/or forward declarations while promoting encapsulation and the reuse of code or data. In computer programming, a header file is a file that allows programmers to separate certain elements of a program's source code into reusable files.
PreprocessorIn computer science, a preprocessor (or precompiler) is a program that processes its input data to produce output that is used as input in another program. The output is said to be a preprocessed form of the input data, which is often used by some subsequent programs like compilers. The amount and kind of processing done depends on the nature of the preprocessor; some preprocessors are only capable of performing relatively simple textual substitutions and macro expansions, while others have the power of full-fledged programming languages.
C syntaxThe syntax of the C programming language is the set of rules governing writing of software in the C language. It is designed to allow for programs that are extremely terse, have a close relationship with the resulting object code, and yet provide relatively high-level data abstraction. C was the first widely successful high-level language for portable operating-system development. C syntax makes use of the maximal munch principle. C data types The C language represents numbers in three forms: integral, real and complex.
PrintfThe printf family of functions in the C programming language are a set of functions that take a format string as input among a variable sized list of other values and produce as output a string that corresponds to the format specifier and given input values. The string is written in a simple template language: characters are usually copied literally into the function's output, but format specifiers, which start with a character, indicate the location and method to translate a piece of data (such as a number) to characters.
Directive (programming)In computer programming, a directive or pragma (from "pragmatic") is a language construct that specifies how a compiler (or other translator) should process its input. Directives are not part of the grammar of a programming language, and may vary from compiler to compiler. They can be processed by a preprocessor to specify compiler behavior, or function as a form of in-band parameterization. In some cases directives specify global behavior, while in other cases they only affect a local section, such as a block of programming code.
String literalA string literal or anonymous string is a literal for a string value in the source code of a computer program. Modern programming languages commonly use a quoted sequence of characters, formally "bracketed delimiters", as in x = "foo", where "foo" is a string literal with value foo. Methods such as escape sequences can be used to avoid the problem of delimiter collision (issues with brackets) and allow the delimiters to be embedded in a string. There are many alternate notations for specifying string literals especially in complicated cases.
Function (computer programming)In computer programming, a function or subroutine is a sequence of program instructions that performs a specific task, packaged as a unit. This unit can then be used in programs wherever that particular task should be performed. Functions may be defined within programs, or separately in libraries that can be used by many programs. In different programming languages, a function may be called a routine, subprogram, subroutine, or procedure; in object-oriented programming (OOP), it may be called a method.
Conditional compilationIn computer programming, conditional compilation is a compilation technique which results in an executable program that is able to be altered by changing specified parameters. This technique is commonly used when these alterations to the program are needed to run it on different platforms, or with different versions of required libraries or hardware. Many programming languages support conditional compilation. Typically compiler directives define or "undefine" certain variables; other directives test these variables and modify compilation accordingly.
OpenMPOpenMP (Open Multi-Processing) is an application programming interface (API) that supports multi-platform shared-memory multiprocessing programming in C, C++, and Fortran, on many platforms, instruction-set architectures and operating systems, including Solaris, AIX, FreeBSD, HP-UX, Linux, macOS, and Windows. It consists of a set of compiler directives, library routines, and environment variables that influence run-time behavior.
Modular programmingModular programming is a software design technique that emphasizes separating the functionality of a program into independent, interchangeable modules, such that each contains everything necessary to execute only one aspect of the desired functionality. A module interface expresses the elements that are provided and required by the module. The elements defined in the interface are detectable by other modules. The implementation contains the working code that corresponds to the elements declared in the interface.
Make (software)In software development, Make is a build automation tool that builds executable programs and libraries from source code by reading s called makefiles which specify how to derive the target program. Though integrated development environments and language-specific compiler features can also be used to manage a build process, Make remains widely used, especially in Unix and Unix-like operating systems. Make can be used to manage any project where some files need to be updated automatically from others whenever the others change in addition to building programs.
Digraphs and trigraphsIn computer programming, digraphs and trigraphs are sequences of two and three characters, respectively, that appear in source code and, according to a programming language's specification, should be treated as if they were single characters. Various reasons exist for using digraphs and trigraphs: keyboards may not have keys to cover the entire character set of the language, input of special characters may be difficult, text editors may reserve some characters for special use and so on.
Sizeofsizeof is a unary operator in the programming languages C and C++. It generates the storage size of an expression or a data type, measured in the number of char-sized units. Consequently, the construct sizeof (char) is guaranteed to be 1. The actual number of bits of type char is specified by the preprocessor macro , defined in the standard limits.h. On most modern computing platforms this is eight bits. The result of sizeof has an unsigned integer type that is usually denoted by size_t.
Conditional (computer programming)In computer science, conditionals (that is, conditional statements, conditional expressions and conditional constructs) are programming language commands for handling decisions. Specifically, conditionals perform different computations or actions depending on whether a programmer-defined Boolean condition evaluates to true or false. In terms of control flow, the decision is always achieved by selectively altering the control flow based on some condition (apart from the case of branch predication).
Variadic macro in the C preprocessorA variadic macro is a feature of some computer programming languages, especially the C preprocessor, whereby a macro may be declared to accept a varying number of arguments. Variable-argument macros were introduced in 1999 in the ISO/IEC 9899:1999 (C99) revision of the C language standard, and in 2011 in ISO/IEC 14882:2011 (C++11) revision of the C++ language standard. Support for variadic macros with no arguments was added in C++20 and will be added in C23.
C++11C++11 is a version of the ISO/IEC 14882 standard for the C++ programming language. C++11 replaced the prior version of the C++ standard, called C++03, and was later replaced by C++14. The name follows the tradition of naming language versions by the publication year of the specification, though it was formerly named C++0x because it was expected to be published before 2010. Although one of the design goals was to prefer changes to the libraries over changes to the core language, C++11 does make several additions to the core language.
Objective-CObjective-C is a high-level general-purpose, object-oriented programming language that adds Smalltalk-style messaging to the C programming language. Originally developed by Brad Cox and Tom Love in the early 1980s, it was selected by NeXT for its NeXTSTEP operating system. Due to Apple macOS’s direct lineage from NeXTSTEP, Objective-C was the standard programming language used, supported, and promoted by Apple for developing macOS and iOS applications (via their respective APIs, Cocoa and Cocoa Touch) until the introduction of the Swift programming language in 2014.