Path: utzoo!utgpu!jarvis.csri.toronto.edu!clyde.concordia.ca!uunet!mcsun!hp4nl!botter!star.cs.vu.nl!maart
From: maart@cs.vu.nl (Maarten Litmaath)
Newsgroups: comp.unix.questions
Subject: Re: use of set in a shell script
Message-ID: <5060@solo9.cs.vu.nl>
Date: 8 Jan 90 21:58:43 GMT
References: <472@cpsolv.UUCP>
Reply-To: maart@cs.vu.nl (Maarten Litmaath)
Organization: VU Informatika, Amsterdam, the Netherlands
Lines: 41

In article <472@cpsolv.UUCP> rhg@cpsolv.UUCP (Richard H. Gumpertz) writes:
\...	set $DIRS
\	find $@ -type f -exec ...
\
\...  Isn't the above
\roughly equivalent to (but slower than)
\	find $DIRS -type f -exec ...
\where the set command has been deleted?  The only difference I can see is that
\the version with the set command will make one more passing unquoting things,
\which could have been avoided using
\	set $DIRS
\	find "$@" -type f -exec ...

What will happen to an unquoted variable?
1)	It is broken up into words at sequences of IFS.
2)	It is globbed.
No unquoting.

\Are there any other subtle differences that I missed?  Is there any way to
\avoid the one pass of unquoting things that seems to remain in either case?

optc=0
optv=

for i
do
	case $i in
	-*)
		optc=`expr $optc + 1`
		eval optv$optc='"$i"'
		optv="$optv \"\$optv$optc\""
		;;
	*)
		# you get the idea
	esac
done

eval set $optv		# restore the options EXACTLY
-- 
1755 EST, Dec 14, 1992: Henry Spencer is put on a one-way mission to the moon.|
  Maarten Litmaath @ VU Amsterdam:  maart@cs.vu.nl,  uunet!mcsun!botter!maart