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How to call "if NOT test; then..."

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# 1  
Old 03-16-2009
Question How to call "if NOT test; then..."
Hi there,
I need to do something if a ping fails:
Code:
if ping -c1 192.168.1.1 > /dev/null 2>&1; then :; else
    echo Ping failed
fi

Can't I just do something like:
Code:
if not ping -c1 192.168.1.1 > /dev/null 2>&1; then
    echo Ping failed
fi

Obviously this doesn't work. What's the syntax for if not?
Thanks for your help
Santiago
# 2  
Old 03-17-2009
you have to do something like this...

Code:
ping -c 2 -s 100 -w 1 ipaddress >/dev/null
if [ $? -eq 1 ] ; then
echo "ping failed"
else
echo "pinging"
fi

# 3  
Old 03-17-2009
Code:
$ ping 192.168.1.1
no answer from 192.168.1.1

$ if ! ping -c1 192.168.1.1 > /dev/null 2>&1; then
> echo ping failed
> fi
ping failed

$ ping 10.68.64.122
10.68.64.122 is alive

$ if ! ping -c1 10.68.64.122 > /dev/null 2>&1; then
> echo ping failed
> fi
$

# 4  
Old 03-17-2009
Thanks vidyadhar for your time and help.
Thanks rikxik for your prop, that's exactly what I was looking for.
# 5  
Old 03-17-2009
If you are using ksh, you can use the short circuit operator:

Code:
ping -c1 192.168.1.1 > /dev/null 2>&1 || echo "ping failed"

# 6  
Old 03-17-2009
Thanks rikxik,
I knew this short circuit and I'm using it with bash.
But I needed your syntax because I have several lines in the if then.
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