Tk_OwnSelection(tkwin, selection, proc, clientData)
Tk_OwnSelection arranges for tkwin to become the new owner of the selection specified by the atom selection. After this call completes, future requests for the selection will be directed to handlers created for tkwin using Tk_CreateSelHandler. When tkwin eventually loses the selection ownership, proc will be invoked so that the window can clean itself up (e.g. by unhighlighting the selection). Proc should have arguments and result that match the type Tk_LostSelProc:
typedef void Tk_LostSelProc(ClientData clientData);The clientData parameter to proc is a copy of the clientData argument given to Tk_OwnSelection, and is usually a pointer to a data structure containing application-specific information about tkwin.