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while loop

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# 1  
Old 09-13-2010
while loop
Hi all,

I have a (I think) rather easy question for you.

I'm trying to put a while loop in my .sc script file. However I have a problem to indicate which statements should be part of the loop and which not.

Currently (part of) my script looks like this:
Code:
while ( $start < $end )
echo "$start"
@ start = ( $start + 2 )
echo "stop"

This results in:
Code:
0
stop
2
stop
..

However, I would like it to be:
Code:
0
2
stop

When looking at internet I found while-loops should look like this:
Code:
while [ condition ]
do
command1
..
done

But this does not work for me..

Anybody knows what I am doing wrong?
Last edited by Scott; 09-13-2010 at 11:54 AM.. Reason: Please use code tags
# 2  
Old 09-13-2010
Hi.

As this appears to be C-shell, the while-loop syntax looks OK.

The while [ condition ] variant is use by sh-derived shells.

What I can't see in your code is the end for the while-loop.

end before "stop" message:
Code:
$ cat CSH1
#!/bin/csh

set start = 0
set end = 4
while ( $start < $end )
  echo "$start"
  @ start = ( $start + 2 )
end
echo "stop"

$ ./CSH1
0
2
stop

end after "stop" message:
Code:
$ cat CSH2
#!/bin/csh

set start = 0
set end = 4
while ( $start < $end )
  echo "$start"
  @ start = ( $start + 2 )
  echo "stop"
end

$ ./CSH2
0
stop
2
stop

There must be an end somwhere otherwise, you'd get this:
Code:
$ cat CSH3
#!/bin/csh

set start = 0
set end = 4
while ( $start < $end )
  echo "$start"
  @ start = ( $start + 2 )
  echo "stop"

$ ./CSH3
0
stop

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