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Function Details : atexit

intatexit(void (*)(void) func) ;

Return Type : int

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

Read about return values of atexit function .

1st Parameter Type : void (*)(void)

Pointer to a function that takes no arguments and returns no value

1st Parameter

Pointer to a function with no parameters and no return value, to be called on program termination

Read more about parameters of atexit in parameters section

The atexitfunction in C language Registers a function to be called at program termination.

The atexit function registers the given function to be called automatically when the program terminates normally. This is useful for performing cleanup operations, closing files, or freeing resources. Multiple functions can be registered, and they will be called in the reverse order of their registration. The registered functions should not use their return value and should not take any parameters.

The atexitfunction takes 1 parameter:

•
void (*)(void) `func`: Pointer to a function with no parameters and no return value, to be called on program termination

Registers a function to be called automatically upon normal program termination. Functions are executed in the reverse order of their registration.

The atexit function return value :

Returns 0 if the function is successfully registered, non-zero if it fails

Output

This example demonstrates registering multiple functions with `atexit`. These functions will be called in reverse order when the program terminates.