Threads and asynchronous I/O (libthread) interfaces

The threads library interfaces (libthread), which include the asynchronous I/O routines, are documented in the Section 3thread manual pages and Section 3aio manual pages, and are available on SCO UnixWare 2.1.X and UnixWare 7 only. These interfaces are not available to UnixWare and OpenServer Development Kit-compiled applications running on SCO OpenServer.

Note that the asynchronous I/O routines on SCO OpenServer that correspond to the routines documented in Section 3aio manual pages are part of libsuds on SCO OpenServer, and are not supported for SCO OpenServer binaries running on UnixWare 7. The libsuds versions of these routines are also not supported by the UnixWare and OpenServer Development Kit.

There are some differences between the implementations of these interfaces on UnixWare 7 and SCO UnixWare 2.1.X:

• In UnixWare 7, multiple requests to aio_memlock(3aio) are permitted during a process's lifetime; each call must specify a different address range. This allows processes to do asynchronous I/O over multiple regions of the address space. Only one call per process is allowed in previous releases of UnixWare.