Inside Macintosh: Networking With Open Transport / Part 2 - Open Transport Reference

Chapter 21 - Providers Reference / Functions

Sending Module-Specific Commands

STREAMS modules can respond to module-specific commands.You can send a module-specific command to an Open Transport protocol module by using the OTIoctl function. Open Transport does not interpret these commands; it merely relays them from your application to the module..

WARNING

Sending module-specific commands is for advanced users only. It can give rise to conflicts for the provider and confuse the endpoint library.