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terminating script with CTRL+D


 
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# 1  
Old 10-24-2006
terminating script with CTRL+D

Hi,

I'm trying to make a script that reads the console input and terminates with CTRL+D. It's absolutely basic but I don't know how to "read" the CTRL+D. I've tried a bunch of things like

Code:
EOT=^D
while [ "$input" != "$EOF" ] //with & without quotations
do
read input
echo $input
done

Code:
while [ "$input" != $'\x04' ] 
while [[ $input != $'\004' ]]

and quite a few others but I just can't make it work.
If anyone could tell me how to do this, I would appreciate the help.
# 2  
Old 10-24-2006
The name for the ctrl-D signal is "eof". If you want to do anything special if/when the user sends a ctrl-D, you'll need to trap it. The syntax in ksh is
Code:
trap cmd sig1 sig2 ...

Code:
trap 'print \'You hit control-D!\'' eof

# 3  
Old 10-24-2006
The read command returns status code 1 at EOF.
Code:
while read input
do
   echo $input
done

Jean-Pierre.
# 4  
Old 10-24-2006
@Glenn Arndt
I am using bash and I looked through the trap sigspecs and couldn't find which signal corresponds to CTRL+D.

@aigles
I've tried the loop you suggested but the problem is that it does not output the value of $input after termination and I would like that to be seen.

Thank you for suggestions. I hope that soon I'll be done with this thing.
# 5  
Old 10-24-2006
Quote:
Originally Posted by sanchopansa
@Glenn Arndt
I am using bash and I looked through the trap sigspecs and couldn't find which signal corresponds to CTRL+D.
Ctrl-D isn't a signal. It closes stdin.
# 6  
Old 10-24-2006
OK. Excuse me for my messed-up terminology, I'm still a beginner.
Would you mind telling me than how can I make a script that reads from stdin closes stdin when CTRL+D is entered and outputs what has been read to stdout?
I understand that I can simply do

read input
echo $input

but I have to press CTRL+D twice to close stdin in this case.

I would appreciate your help and I am sorry if my incompetence is making you nervous.
# 7  
Old 10-24-2006
Quote:
Originally Posted by sanchopansa
@aigles
I've tried the loop you suggested but the problem is that it does not output the value of $input after termination and I would like that to be seen.
After termination (CTRL-D) the variable $input is empty.
Code:
while read input
do
   echo "Input value: $input"
done
echo "We are at EOF"


Jean-Pierre.

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