String comparison in while [ ... ] condition

hiwa · 05-27-2007, 12:23 AM

Code:

# if user input is a 'y', repeat the process
a="y"
while [ $a=y ]
do
 read a
 echo "Bang! $a"
done

In the above script,
while [ $a=y ]
while [ $a="y" ]
while [ "$a"=y ]
while [ "$a"="y" ]
while [ $a='y' ]
etc., etc. all fails. I'm completely stuck.

What could be the correct syntax and why?

daihard · 05-27-2007, 12:53 AM

It needs to be:

Code:

while [ "$a" = "y" ]

Apparently bash requires white spaces around the equal sign.

hiwa · 05-27-2007, 01:17 AM

That works. Thanks!
It tormented me more than a half day today!

daihard · 05-27-2007, 02:05 AM

Quote:

Originally Posted by hiwa

That works. Thanks!
It tormented me more than a half day today!

Glad it helped. Otsukare-sama.