Files
pcas/src/cas/RELEASE_NOTES
Jeff Hill 3f7bfda8d8 doc
1996-11-07 14:42:36 +00:00

64 lines
2.4 KiB
Plaintext

Changes between epics 3.13 Beta 3 and 3.13 Beta 4
**** API Changes ****
o The canonical PV name is returned from caServer::pvExistTest()
in the supplied buffer and not in a gdd data descriptor. See
"casdef.h".
old API:
//
// pvExistTest()
//
// The server tool is encouraged to accept multiple PV name
// aliases for the same PV here. However, a unique canonical name
// must be selected for each PV.
//
// returns S_casApp_success and fills in canonicalPVName
// if the PV is in this server tool
//
// returns S_casApp_pvNotFound if the PV does not exist in
// the server tool
//
// The server tool returns the unique canonical name for
// the pv into the gdd. A gdd is used here becuase this
// operation is allowed to complete asynchronously.
//
virtual caStatus pvExistTest (const casCtx &ctx, const char *pPVName,
gdd &canonicalPVName) = 0;
new API:
//
// pvExistTest()
//
// The server tool is encouraged to accept multiple PV name
// aliases for the same PV here. However, one unique canonical name
// must be selected by the srever tool and returned to the
// server lib for each PV. The server will use this canonical
// name to prevent internal duplication of data structures for
// process variables that have multiple aliases.
//
// o returns S_casApp_success and a valid canonical name string
// when the PV is in this server tool
//
// o returns S_casApp_pvNotFound if the PV does not exist in
// the server tool
//
// Examples:
// caServerXXX::pvExistTest(const casCtx &ctx, const char *pPVName)
// {
// return pvExistReturn(S_casApp_success, pPVName); // common
// return pvExistReturn(S_casApp_pvNotFound); // no PV by that name
//
// char pName[9] = "myPVName";
// return pvExistReturn(S_casApp_success, pName); // also common
// return pvExistReturn(S_casApp_asyncCompletion); // not now
// }
//
virtual pvExistReturn pvExistTest (const casCtx &ctx,
const char *pPVName)=0;
o The server tool must now use one of class casAsyncReadIO, casAsyncWriteIO, or
casAsyncPVExistIO in place of casAsyncIO. See "casdef.h".