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Function Details : toupper

inttoupper(int c) ;

Return Type : int

Integer type (typically 4 bytes, -2,147,483,648 to 2,147,483,647)

Read about return values of toupper function .

1st Parameter Type : int

Integer type (typically 4 bytes, -2,147,483,648 to 2,147,483,647)

1st Parameter

The character to be converted to uppercase. This is passed as an `int` to allow handling of `EOF` or extended character values.

Read more about parameters of toupper in parameters section

The toupperfunction in C language Converts a character to uppercase.

The toupper function converts a lowercase letter to the corresponding uppercase letter. If the argument is not a lowercase letter, it is returned unchanged. This function is commonly used for case conversion in text processing or to ensure consistent casing in certain applications.

The toupperfunction takes 1 parameter:

•
int `c`: The character to be converted to uppercase. This is passed as an `int` to allow handling of `EOF` or extended character values.

Converts the given character `c` to its uppercase equivalent if it is a lowercase letter. If `c` is not a lowercase letter, the function returns `c` unchanged. The behavior is undefined if `c` is not representable as an `unsigned char` and is not equal to `EOF`.

The toupper function return value :

If c is a lowercase letter, returns the corresponding uppercase letter
Otherwise, it returns c unchanged

Output

This example demonstrates toupper on both lowercase and uppercase letters.