question about "if" in script

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12-16-2010

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question about "if" in script

Code:

if ping -q -c 4 www.google.com>/dev/null ;then

    echo "ok";     

fi

how exactly the expression in the is evaluated?

programAngel

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12-16-2010

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This way not at all.
Try:

Code:

ping -q -c 4 www.google.com > /dev/null 2>&1
if [ $? = 0 ]; then
     echo ok
fi

# a shorter version
ping -q -c 4 www.google.com > /dev/null 2>&1 && echo ok

zaxxon

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