C Identifiers

Definition:

Identifiers are sequences of characters used for naming variables, functions, new data types, and preprocessor macros.

Rules:

• Identifier can be include letters uppercase(A-Z) and lowercase(a-z)
• Identifier can be decimal digits(0-9).
• The first character of an identifier cannot be a digit.
• You Can Include underscore character ?_? in identifiers.The first character of an identifier cannot be an underscore(Some Compilers Accept underscore as a first Character).
• Lowercase letters and uppercase letters are distinct, such that foo and FOO are two different identifiers.
• When using GNU extensions, you can also include the dollar sign character ?$? in identifiers.

Syntax

data_type name_of_identifeir // Variable name

data_type name_of_function(......)// function name

Identifiers Example

// Variable
int amount;
char name[20];

// Function
void calculation(int a,int b){
}

Related Pages

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• C Tutorials — Browse all C Tutorials.
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• C Specific Properties and Implementation — More in c basics.