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Function Details : isalnum

intisalnum(int c) ;

Return Type : int

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

Read about return values of isalnum 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 tested, passed as an `unsigned char` cast to an `int`, or `EOF`

Read more about parameters of isalnum in parameters section

The isalnumfunction in C language Checks whether the character is alphanumeric.

The isalnum function tests whether c is a character for which isalpha or isdigit is true. The behavior is undefined if the value of c is not representable as unsigned char and is not equal to EOF.

The isalnumfunction takes 1 parameter:

•
int `c`: The character to be tested, passed as an `unsigned char` cast to an `int`, or `EOF`

Checks if the given character `c` is an alphanumeric character (a letter or a digit). Returns a nonzero value if `c` is alphanumeric, and `0` otherwise.

The isalnum function return value :

Returns non-zero if the character is alphanumeric, 0 otherwise

Output

This example demonstrates basic usage of isalnum with various characters.