WordPress at a glance
action is not described

manage_(post_type)_posts_custom_column action-hook . WP 3.1.0

Fires for each custom column of a specific post type in the Posts list table.

The dynamic portion of the hook name, $post->post_type, refers to the post type.

Usage

add_action( 'manage_(post_type)_posts_custom_column', 'action_function_name_5242', 10, 2 );
function action_function_name_5242( $column_name, $post_id ){
	// action...
}
$column_name(string)
The name of the column to display.
$post_id(int)
The current post ID.

Where the hook is called

WP_Posts_List_Table::column_default()
wp-admin/includes/class-wp-posts-list-table.php 1162
do_action( "manage_{$post->post_type}_posts_custom_column", $column_name, $post->ID );

Where the hook is used (in WP core)

Does not used.