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filter is not described

pre_post_(field) filter-hook . WP 2.3.0

Filters the value of a specific field before saving.

The dynamic portion of the hook name, $field_no_prefix, refers to the post field name.


add_filter( 'pre_post_(field)', 'filter_function_name_9003' );
function filter_function_name_9003( $value ){
	// filter...

	return $value;
Value of the post field.

Where the hook is called

wp-includes/post.php 2364
$value = apply_filters( "pre_post_{$field}", $value );

Where the hook is used (in WP core)

wp-includes/default-filters.php 95
add_filter( 'pre_post_mime_type', 'sanitize_mime_type' );