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Ctrl-C untrap?

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# 1  
Old 05-10-2015
Ctrl-C untrap?
Hi guys...

I know how to trap Ctrl-C, that is easy and I have even done it obfuscated...

However once the trapping is enbaled how can the trapped Ctrl-C be returned to normal again? Google is not my friend here...

Reason, the recent Scope upload will hang awaiting a signal in EXT TRIG mode and Ctrl-C would be a good way of escaping this section without stopping the program completely...

TIA...
# 2  
Old 05-10-2015
Hi Barry, try:
Code:
trap - SIGINT

Last edited by Scrutinizer; 05-10-2015 at 08:57 AM..
These 2 Users Gave Thanks to Scrutinizer For This Post:
sea wisecracker
# 3  
Old 05-10-2015
My first (un-)trap attempt:
Code:
trap 'exit 130' SIGINT

hth
# 4  
Old 05-10-2015
Hi Scrutinizer...

Excellent many thanks, worked a treat...

Test code for others to try:-
Code:
#!/bin/bash
function Ctrl_C() { echo " You can't do that... :oD"; }
trap Ctrl_C SIGINT
for n in {0..10}
do
	echo "You are in the for loop."
	sleep 1
done
trap - SIGINT
while true
do
	echo "Escape loop..."
	sleep 1
done

Results:-
Code:
Last login: Sun May 10 13:03:47 on ttys000
AMIGA:barrywalker~> cd Desktop/Code/Shell
AMIGA:barrywalker~/Desktop/Code/Shell> ./trap.sh
You are in the for loop.
You are in the for loop.
^C You can't do that... :oD
You are in the for loop.
^C You can't do that... :oD
You are in the for loop.
^C You can't do that... :oD
You are in the for loop.
^C You can't do that... :oD
You are in the for loop.
^C You can't do that... :oD
You are in the for loop.
^C You can't do that... :oD
You are in the for loop.
^C You can't do that... :oD
You are in the for loop.
^C You can't do that... :oD
You are in the for loop.
You are in the for loop.
Escape loop...
Escape loop...
Escape loop...
Escape loop...
^C
AMIGA:barrywalker~/Desktop/Code/Shell> _

Again many thanks...
This will be implemented in the next Scope upload...

EDIT:

Just realised bash has the 'help' command and it is in there! DOH!
Changed the line to 'trap - SIGINT'
Last edited by wisecracker; 05-10-2015 at 09:29 AM.. Reason: See above...
This User Gave Thanks to wisecracker For This Post:
RudiC
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