The GDI library provides the priority-queue data type that is used with device-specific fonts to sort output strings into the correct order on the page. Priority queues are accessed through a two-byte value, known as the key. Each key can also have two bytes of associates information, called a tag.
The following lists the priority-queue functions, and provides a brief description of each.
| Function | Description |
| CreatePQ | Creates a priority queue. |
| DeletePQ | Deletes a priority queue. |
| InsertPQ | Inserts a key in a priority queue. |
| MinPQ | Returns the tag having the smallest key in the queue. |
| SizePQ | Sets the size of the priority queue. |
| ExtractPQ | Extracts a key from a priority queue. |