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  +0       2  wRecLength   size of this structure, in bytes (10)
  +2       2  wApiType     type of asynchronous API supported by program
  +4       2  wVerMajor    version number (major) eg with "3.10", use 0003H
  +6       2  wVerMinor    version number (minor) eg with "3.10", use 000aH
  +8       2  wSupportLvl  code 0000H-0004H (see below)
          10               size of a SwApiInfoRec structure

    wApiType  this code identifies API protocol supported by an application.
              It must be one of:
                0001H   NETBIOS
                0002H   802.2
                0003H   TCP/IP
                0004H   Lan Manager named pipes
                0005H   NetWare APX

 wSupportLvl  this code identifies how much support this program provides
              for the API specified in wApiType.  It is one of:

              0001H   Minimal support.  Program prevents a session switch
              after an API call is made (e.g., DOS's InterLink).

              0002H   API-level support.  The program prevents switching
              while requests remain to be processed; but enables switching
              when all request are completed.

              0003H  Switcher compatibility.  Allows switching even when
              unfinished requests are outstanding; but this may be limited
              by internal constraints such as buffer sizes, etc..

              0004H  Seamless compatibility.  Allows switching at any time.

 This structure is used in SwSrvcFn 0006H (query API support).  It enables
 API handlers to determine which program supplies the highest level of
 support for asynchronous task-switching API services.

 It is also referred to in SwCallbackInfoRecs.  A series of these
 structures may exist for each client program that provides task-switching
 API support--one for each supported API.  The list ends when the
 wRecLength field is 0000H.

See Also: Switcher Services and Notifications
          INT 2fH 4bxxH (switcher functions)