command line options

Root Boy Jim rbj at icst-cmr.arpa
Mon Apr 11 12:37:23 AEST 1988


   From: Arthur David Olson <ado at elsie.uucp>

   3.  I want to be able to find out if "--" was used on the command line.

       Pike's Position is that
		   Programs that accept multiple filenames
		   should do nothing if given no arguments.
       (The name and wording are mine; see page 186 of "The UNIX Programming
       Environment").  This ensures that if you use a command such as
			   cat `find * -type f -print`
       to concatenate all the files in a directory and its subdirectories,
       you won't get surprised when there are NO files in the directory and
       cat starts reading from its standard input.

Add /dev/null to the end. This trick is also used in the GNU emacs `grep'
command. They add /dev/null to the end so that grep will tell which file
it was found in, even if there was only one specified.

	(Root Boy) Jim Cottrell	<rbj at icst-cmr.arpa>
	National Bureau of Standards
	Flamer's Hotline: (301) 975-5688
There's enough money here to buy 5000 cans of Noodle-Roni!



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