Usage
#define ACPI_USAGE_HEADER(Usage) \
printf ("Usage: %s\nOptions:\n", Usage);
uint32 Usage() { return fUsage; };
item->Usage());
printf(Usage(), commandName);
const char* Usage() const { return fUsage; }
Usage();
extern void Usage();
Usage(programName);
void Usage(const char *programName);
Usage();
void Usage(void);
Usage(string(" "));
Usage(string("Unknown command `") + command + "'");