UNIX for Dummies Questions & Answers

Hey guys...

I'm learning some shell scripting on OS X using the tcsh shell.

For some reason... my while loop isn't executing right (or more likely I am doing something wrong.)

Something as simple as this doesn't work:

Code:

#!/bin/tcsh

set g = 0

while ($g <10)

echo "this" $g

@ g = $g + 1

end

By doesn't work, I mean it goes through the first time and then stops.

If I type it in to the terminal it works fine. But if I write it in a text editor (BBEdit) and save it as a script, then execute (after making it executable) it only goes through the first iteration.

The WEIRDEST part is that if I nest a while loop inside of it with the exact same syntax, the inner loop works correctly, while the outer loop still only goes through once.

Little help?

Robert

Well, your code works under Solaris tcsh with no problem.

Are you getting any kind of error? Try the following - maybe it's dumping out and you aren't getting any error message.

Code:

#!/bin/tcsh

set g = 0
echo "should be zero - $g"
while ($g <10)

echo "this" $g

@ g = $g + 1
echo "should be plus 1  - $g"
end
echo "end of script"

I ran the script on Solaris and on Linux it worked with the statement 'echo "end of script"' at the end. It also worked even if this statement was commented. So I deleted the words in that line leaving out a blank line after end statement. The script still worked. But only when I remove the last line and leave nothing after end it stops looping.
#!/bin/tcsh
set g = 0
while ($g <10)
echo "this" $g
@ g = $g + 1
echo "should be plus 1 - $g"
end #Doesn't work


#!/bin/tcsh
set g = 0
while ($g <10)
echo "this" $g
@ g = $g + 1
echo "should be plus 1 - $g"
end
#Does work. Notice that this introduces a new line character after end above