[#BloombergLP-balb-ControlManager-registerDefaultHandler] = xref:BloombergLP.adoc[BloombergLP]::xref:BloombergLP/balb.adoc[balb]::xref:BloombergLP/balb/ControlManager.adoc[ControlManager]::registerDefaultHandler :relfileprefix: ../../../ :mrdocs: Register the specified `handler` to be invoked whenever a control message having an unregistered (case‐insensitive) `prefix` is received by this control manager. Return a positive value if an existing callback was replaced, return 0 if no replacement occurred, and return a negative value otherwise. == Synopsis Declared in `<balb_controlmanager.h>` [source,cpp,subs="verbatim,replacements,macros,-callouts"] ---- int registerDefaultHandler(xref:BloombergLP/balb/ControlManager/ControlHandler.adoc[ControlHandler] const& hander); ---- [.small]#Created with https://www.mrdocs.com[MrDocs]#