This is a 32 bit bitmap similar to TXC.FMAPCTL except that it specifies which function keys are to be sent to the application. (This requires that the TXF_FKEYS flag be set). Such keys will cause the control to exit with exitcode set to -1 through -16 and -17 through -32 for F1 through F16 and Shift+F1 through Shift+F16 respectively.
