Performs the same as ctListAdd, but with 2 additional new arguments. Adds a tag, or tag element, to the list. Once the tag has been added to the list, it may be read using ctListRead() and written to using ctListWrite(). If a read is already pending, the tag will not be read until the next time ctListRead() is called. ctListWrite() may be called immediately after the ctListAdd() function has completed.
If ctListAdd is called instead of ctListAddEx, The poll period of the subscription for the tag defaults to 500 milliseconds, and the bRaw flag defaults to the engineering value of FALSE.
ctListAddEx(hList, sTag, bRaw, nPollPeriodMS, dDeadband)
Description: The handle to the list, as returned from ctListNew().
Description: The tag or tag name and element name, separated by a dot to be added to the list. If the element name is not specified, it will be resolved at runtime as for an unqualified tag reference.
Description: Specifies whether to subscribe to the given tag in the list using raw mode if TRUE or engineering mode if FALSE.
Description: Dictates the poll period used in the subscription made for the tag (in milliseconds).
Description: Percentage of the variable tag's engineering range that a tag needs to change by in order for an update to be sent through the system. A value of -1.0 indicates that the default deadband specified by the tag definition is to be used.
If the function succeeds, the return value specifies a handle. If the function does not succeed, the return value is NULL. To get extended error information, call GetLastError()
If a tag not currently defined in your system is specified using this function then the return value will specify a valid handle. Calling ctListRead will allow identification of the true state of the tag. Passing an empty tag to this function will result in the function exiting immediately and returning NULL.
ctOpen, ctListNew, ctListFree, ctListRead, ctListWrite, ctListData, ctListItem