Re: [PATCH] Fixed non portable use of expr and removed incorrect use of test -eq for string comparison

From: Uwe Kleine-König <ukleinek@informatik.uni-freiburg.de>
Date: Aug 23, 2007, 08:58 UTC
Message-ID: <20070823085808.GA6573@informatik.uni-freiburg.de>
In-Reply-To: <11878139102715-git-send-email-david@olrik.dk>

Hello,

David Jack Olrik wrote:

Show 11 quoted lines

> On 22/08/2007, at 15.23, Uwe Kleine-König wrote:
> 
> > > You'd then need to check against 2 instead of 1, which I find less
> > > obvious as we are testing for a '/' at the begining of the string.
> > If I understood the problem right you only need to test for the exit
> > code, that is the program test is not required at all.
> 
> Ah, yes that's true. The following should make it more clear that we are
> looking at the first character.
> 
>     if expr "$httpd_only" : "\/" >/dev/null

yet another note: I used expr "z$http_only" on purpose. Look what happens here:

	$ httpd_only=substr
	$ expr "$httpd_only" : "\/"
	expr: syntax error

Once more, Solaris is more exacting:

	$ /usr/bin/expr "/" : "\/"
	expr: syntax error

(This works fine with GNU expr.)

So better use "z$variable" because (up to now) there is no operator that starts with a 'z'.

Best regards Uwe

-- 
Uwe Kleine-König

fib where fib = 0 : 1 : zipWith (+) fib (tail fib)