status.i4.v = bpm_machine_c(machine.i4.v)

	This routine sets a particular machine for BPM data acquisition.
	This determines which BPM data will be retrieved or saved on
	subsequent bpm_XXX calls.

	machine		sets which machine that you'll get data for
			(BPM_BOOSTER -> Booster,
			 BPM_8_GEV_LINE -> MI-8 Line,
			 BPM_MAIN_INJECTOR -> Main Injector,
			 BPM_MI_DEVL -> Main Injector development,
			 BPM_MI_ABORT_LINE -> Main Injector abort line,
			 BPM_MI_BLT -> Main Injector BLT,
			 BPM_P1_LINE -> P1 Line,
			 BPM_P2_LINE -> P2 Line,
			 BPM_P3_LINE -> P3 Line,
			 BPM_A1_LINE -> A1 Line,
			 BPM_RECYCLER -> Recycler,
			 BPM_RR_DEVL -> Recycler development,
			 BPM_RR_ABORT_LINE -> Recycler abort line,
			 BPM_RR_TO_MI_LINE -> Recycler to Main Injector line,
			 BPM_R20_LINE -> R20 Line,
			 BPM_R30_LINE -> R30 Line,
			 BPM_RECYCLER_BLT -> Recycler BLT,
			 BPM_TEVATRON -> Tevatron,
			 BPM_TEV_DEVL -> Tevatron development,
			 BPM_AP1_LINE -> AP1 Line,
			 BPM_AP1_LINE_DEVL -> AP1 Line development,
			 BPM_AP2_LINE -> AP2 Line,
			 BPM_AP3_LINE -> AP3 Line,
			 BPM_MINIBOONE -> MiniBooNE line,
			 BPM_ELECTRON_COOLING -> Electron Cooling,
			 BPM_EC_DEVL -> Electron Cooling (development),
			 BPM_ACCUMULATOR -> Accumulator,
			 BPM_400_MEV -> 400 MeV Line,
			 BPM_NUMI -> NuMI beam line,
			 BPM_MTA -> MTA (Muon Test Area),
			 BPM_M1_LINE -> M1 Line,
			 BPM_M3_LINE -> M3 Line,
			 BPM_DELIVERY_RING -> Delivery Ring,
			 BPM_M5_LINE -> M5 Line,
			 CLIB_DEFAULT_ARG -> return current machine only)

	This function returns ACNET status values as follows:

	CBS_INVARG		invalid machine selected
	otherwise		previously selected machine

	This function requires the following include files:

	ul_cbsaux/bpmuti.h, acnet_errors_h

	Related functions:

	bpm_get_data_c, blm_get_data_c, bpm_get_intensity_c, bpm_save_data,
	bpm_set_save_file, bpm_file_menu_c

	C/C++ usage:

	int	status;
	int	machine = BPM_TEVATRON;

	status = bpm_machine_c(machine);