Offset Size Contents
+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:
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.

INT 2fH 4bxxH (switcher functions)
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