Showing errors individually in CodeIgniter

In CodeIgniter framework  validation_errors() is function to display form errors in at the form.
<?php echo validation_errors(); ?>

To display errors individually the below is the example view program script

<h5>Username</h5>
<?php echo form_error('username'); ?>
<input type="text" name="username" value="<?php echo set_value('username'); ?>" size="50" />

<h5>Password</h5>
<?php echo form_error('password'); ?>
<input type="text" name="password" value="<?php echo set_value('password'); ?>" size="50" />

<h5>Password Confirm</h5>
<?php echo form_error('passconf'); ?>
<input type="text" name="passconf" value="<?php echo set_value('passconf'); ?>" size="50" />

<h5>Email Address</h5>
<?php echo form_error('email'); ?>
<input type="text" name="email" value="<?php echo set_value('email'); ?>" size="50" />