Used as the synchronization point for asynchronous I/O system
    services. This routine is for OpenVMS systems only.

1  –  C Binding

    #include <tis.h>

    int
    tis_sync (
          unsigned long   efn,
          void   *iosb);

2  –  Arguments

 efn

    The event flag specified with the OpenVMS system service routine.

 iosb

    The IOSB specified with the OpenVMS system service routine.

3  –  Description

    When you are performing thread-synchronous "wait-form" system
    service calls on OpenVMS such as $QIOW, $ENQW, $GETJPIW, and so
    on, you should use this routine and tis_io_complete() with the
    asynchronous form of the service (that is, without the "W") and
    specify the address of tis_io_complete() as the completion AST
    routine (the AST argument, if any, is ignored). The call must
    also specify an IOSB (or equivalent, such as an LKSB) and if
    possible a unique event flag (see lib$get_ef). Once the library
    code is ready to wait for the I/O, it simply calls tis_sync()
    (just as if it were calling $SYNC).

4  –  Return Values

    This routine has the same return values as the OpenVMS $SYNC()
    routine.

5  –  Associated Routines

       tis_io_complete()