Suppress warning message when no keyword patterns are found.
If file prog.c is compiled, and it contains this line of code:
char rcsID = "$Author: george $
then the following output is produced:
ident prog.c prog.oprog.c: $Author: george $ prog.o: $Author: george $
Show keywords for all RCS files (suppress warnings):
co -p RCS/*,v | ident -q