This function sets options that control the behavior of the source control plug-in.
The source control plug-in implementation of this function is expected to return one of the following values:
The option was successfully set.
Returned if nOption was SCC_OPT_SHARESUBPROJ and the source control plug-in allows the IDE to set the destination folder.
The option was not set and should not be relied upon.
The IDE calls this function to control the behavior of the source control plug-in. The first parameter, nOption, indicates the value that is being set, while the second, dwVal, indicates what to do with that value. The plug-in stores this information associated with a pvContext, so the IDE must call this function after calling the SccInitialize Function (but not necessarily after each call to the SccOpenProject Function).
Summary of the options and their values:
Enables/disables background event queuing.
Specifies a user value to be passed to the OPTNAMECHANGEPFN callback function.
Indicates whether the IDE currently supports canceling an operation.
Pointer to the OPTNAMECHANGEPFN callback function
Sets a pointer to a name-change callback function.
Indicates whether the IDE allows the checking out of its files manually (through the source control user interface) or whether they must be checked out only through the source control plug-in.
If the source control plug-in allows the IDE to specify the local project folder, the plug-in returns SCC_I_SHARESUBPROJOK.
If nOption is SCC_OPT_EVENTQUEUE, the IDE is disabling (or re-enabling) background processing. For instance, during a compile, the IDE might instruct the source control plug-in to stop on-idle processing of any kind. After the compile, it would re-enable background processing to keep the plug-in's event queue up to date. Corresponding to the SCC_OPT_EVENTQUEUE value of nOption, there are two possible values for dwVal, namely, SCC_OPT_EQ_ENABLE and SCC_OPT_EQ_DISABLE.
If the value for nOption is SCC_OPT_HASCANCELMODE, the IDE allows users to cancel long operations. Setting dwVal to SCC_OPT_HCM_NO (the default) indicates that the IDE has no cancel mode. The source control plug-in must offer its own Cancel button if it wants the user to be able to cancel. SCC_OPT_HCM_YES indicates that the IDE provides the ability to cancel an operation, so the SCC plug-in does not need to display its own Cancel button. If the IDE sets dwVal to SCC_OPT_HCM_YES, it is prepared to respond to SCC_MSG_STATUS and DOCANCEL messages sent to the lpTextOutProc callback function (see LPTEXTOUTPROC). If the IDE does not set this variable, the plug-in should not send these two messages.
If nOption is set to SCC_OPT_NAMECHANGEPFN, and both the source control plug-in and the IDE allow it, the plug-in can actually rename or move a file during a source control operation. The dwVal will be set to a function pointer of type OPTNAMECHANGEPFN. During a source control operation, the plug-in can call this function, passing in three parameters. These are the old name (with fully qualified path) of a file, the new name (with fully qualified path) of that file, and a pointer to information that has relevance to the IDE. The IDE sends in this last pointer by calling SccSetOption with nOption set to SCC_OPT_USERDATA, with dwVal pointing to the data. Support for this function is optional. A VSSCI plug-that uses this ability must initialize its function pointer and user data variables to NULL, and it must not call a rename function unless it has been given one. It should also be prepared to hold the value it was given or to change it in response to a new call to SccSetOption. This will not happen in the middle of a source control command operation, but it may happen between commands.
If nOption is set to SCC_OPT_SCCCHECKOUTONLY, the IDE is indicating that the files in the currently open project should never be checked out manually through the source control system's user interface. Instead, the files should be checked out only through the source control plug-in under IDE control. If dwValue is set to SCC_OPT_SCO_NO, it means that the files should be treated normally by the plug-in and can be checked out through the source control UI. If dwValue is set to SCC_OPT_SCO_YES, then only the plug-in is allowed to check out files, and the source control system's UI should not be invoked. This is for situations where the IDE might have "pseudo-files" that make sense to check out only through the IDE.
If nOption is set to SCC_OPT_SHARESUBPROJ, the IDE is testing whether the source control plug-in can use a specified local folder when adding files from source control. The value of the dwVal parameter does not matter in this case. If the plug-in allows the IDE to specify the local destination folder where the files will be added from source control when the SccAddFromScc Function is called, then the plug-in must return SCC_I_SHARESUBPROJOK when the SccSetOption function is called. The IDE then uses the lplpFileNames parameter of the SccAddFromScc function to pass in the destination folder. The plug-in uses that destination folder to place the files added from source control. If the plug-in does not return SCC_I_SHARESUBPROJOK when the SCC_OPT_SHARESUBPROJ option is set, the IDE assumes that the plug-in is able to add files only in the current local folder.