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External variable

In the C programming language, and its predecessor B, an external variable is a variable defined outside any function block. On the other hand, a local (automatic) variable is a variable defined inside a function block.

Definition, declaration and theexternkeyword, Scope, lifetime and thestatickeyword & Overview

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Definition, declaration and theexternkeyword

CompilerHeader filesAutomaticFunction prototype
4 related topics

Scope, lifetime and thestatickeyword

Global variableStatickeywordLocal variableFunction pointer
4 related topics

Overview

C programming languageFortranPascalThe C Programming Language
4 related topics

Topics to explore

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Overview

Definition, declaration and theexternkeyword

Scope, lifetime and thestatickeyword

Advanced semantic analysis

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Map overview Semantic statistics

External variable

Nodes16
Edges15
Triples19
Avg. degree1.88
Density0.125
Components1

How this topic connects Entity context

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External variable

Top relations

related to extern · 8
External variable → But, If, In, It, The, Theexternkeyword, To, When
related to Scope, lifetime and thestatickeyword · 7
External variable → An, But, For, In, It, Or, The
related to extrn · 3
External variable → An, In, Using
is a · 1
External variable → variable defined outside any function block

Important terminology Word statistics

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Important terminology

variable function external defined definition declaration variables functions name declared compiler must program also programming language automatic local module outside

Entity relationships Subject–Predicate–Object triples

SubjectPredicateObjectConfidenceSrc
External variableis avariable defined outside any function block0.90text
External variablerelated to externTo0.60section
External variablerelated to externWhen0.60section
External variablerelated to externThe0.60section
External variablerelated to externTheexternkeyword0.60section
External variablerelated to externIn0.60section
External variablerelated to externIt0.60section
External variablerelated to externIf0.60section
External variablerelated to externBut0.60section
External variablerelated to extrnIn0.60section
External variablerelated to extrnAn0.60section
External variablerelated to extrnUsing0.60section

Related concept clusters Concept neighborhoods

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    Connections between topic areas Semantic bridges

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    Min side: 3
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