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Need Help for "until" construction

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Top Forums Shell Programming and Scripting Need Help for "until" construction
# 8  
Old 11-01-2009
Indeed, since the OP's statement would not work. It would work with a while statement. The code to exit is 2 according to his menu. So a while loop would loop while the condition is not equal to 2, whereas an until loop loops until the condition equals 2.
# 9  
Old 11-01-2009
it's a weird loop.
with -ne : it will never enter the loop because 0 -ne 0 returns FALSE
with -eq : it will loop infinitely because 0 -eq 0 always returns TRUE and that $op is never modified.
# 10  
Old 11-01-2009
That's right, that is why I used this:
Code:
until [ $op -eq 2 ]

It seems pretty straight forward to me...
# 11  
Old 11-02-2009
I hope this loop is clear to you now guys... Smilie
BR
# 12  
Old 11-02-2009
Indeed, it is like
Code:
until false; do
done

It really does not matter what you put there as long as it evaluates to false.
Only now I noticed the OP was also mixing up q and op Smilie. Besides. If 2 selects an exit statement then Oh well..

But your code still would not work because of the erroneous assigment:
Code:
op = 0

which should be:
Code:
op=0

Last edited by Scrutinizer; 11-02-2009 at 03:53 AM..
# 13  
Old 11-02-2009
yes you are right:- where niki22 code will not work unless he doing op=0 not op = 0

BR
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