Header File

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. Header files commonly contain forward declarations of classes, subroutines, variables, and other identifiers. Programmers who wish to declare standardized identifiers in more than one source file can place such identifiers in a single header file, which other code can then include whenever the header contents are required. This is to keep the interface in the header separate from the implementation. The C standard library and C++ standard library traditionally declare their standard functions in header files.

More recently created compiled languages (such as Java, C#) do not use forward declarations; identifiers are recognized automatically from source files and read directly from dynamic library symbols. This means header files are not needed.

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Other articles related to "header file, file, files, header, header files, headers":

Opaque Pointer - Examples - C++
... header file class Handle { private struct CheshireCat // Not defined here CheshireCat* smile // Handle public Handle // Constructor Handle(const Handle ... CPP file #include "handle.h" struct HandleCheshireCat { int a int b } HandleHandle smile(new CheshireCat) { // do nothing } HandleHandle(const Handle other) smile(new ... does not affect binary compatibility (c) the header file containing the class declaration only needs to #include those other files needed for the class interface, rather than for ...
Versit Consortium - Computer Telephony Integration
... Volume 5, CTI Protocols Volume 6, Versit TSAPI Appendices include Versit TSAPI header file Protocol 1 ASN.1 description Protocol 2 ASN.1 description Versit ...
List Of File Formats (alphabetical) - H
... Description Used by H! On-line help file Flambeaux Help! Display Engine H! Pertext database HELP.EXE H-- C—language header Sphinx C-- H Header file (usually C language) Watcom C/C++ H++ Header ... graphics file almost JPEG Image Alchemy HST History file Procomm Plus HTM see HTML HTML Hypertext Markup Language (WWW) Netscape - Mosaic - many HTX Hypertext file HWA Hollywood ...
Header File - Alternatives
... Some newer languages (such as Java) dispense with header files and instead use a naming scheme that allows the compiler to locate the source files ... COBOL and RPG IV have a form of include files called copybooks ... source of the program in a similar way to header files, but they also allow replacing certain text in them with other text ...
Unistd.h
... In the C and C++ programming languages, unistd.h is the name of the header file that provides access to the POSIX operating system API ... In Cygwin, a header file can be found in /usr/include that sub-includes a file of the same name in /usr/include/sys ... are done by references to the GNU C standard library headers (like stddef.h) which provide the type size_t and many more ...

Famous quotes containing the word file:

    I have been a soreheaded occupant of a file drawer labeled “Science Fiction” ... and I would like out, particularly since so many serious critics regularly mistake the drawer for a urinal.
    Kurt Vonnegut, Jr. (b. 1922)