Drupal 6 confirm form example

/**
 * Implements hook_menu().
 */
function MYMODULE_menu() {
  $items = array();
  $items['MYMODULE/do-something'] = array(
    'type' => MENU_CALLBACK,
    'access arguments' => array('access content'),
    'page callback' => 'drupal_get_form',
    'page arguments' => array('MYMODULE_confirm_form'),
  );
 
  return $items;
}
 
/**
 * Confirm form example
 */
function MYMODULE_confirm_form($form_state) {
 
  //you can pass variables here if need be
  $form['_my_var'] = array(
    '#type' => 'value',
    '#value' => 'MY Variable',
  );
 
  //you can set a redirect if needed
  $form['#redirect'] = 'user';
 
  return confirm_form($form,
    t('Are you sure you want to do something?'), //message title
    isset($_GET['destination']) ? $_GET['destination'] : 'user', //redirect if cancelled
    t('Only say yes if you are really sure.'), //message description
    t('Lets Do it!'), //confirm button text
    t('Cancel') //cancel button text
  );
}
 
/**
 * Submit handler for confirm form
 */
function MYMODULE_confirm_form_submit($form, &$form_state) {
	//verify that the form was confirmed
  if ($form_state['values']['confirm']) {
    //Do something here
 
    //set a message
    drupal_set_message('You did something!');
 
  }
}