Ensuring that the IP has no strange characters

echo ${IP} | sed "s/[0-9\.]//g"
This command validates if exist any character different in 0-255 and dot. If any characters different is typed the error menssage is showing.
Sample Output
checking=`echo ${IP} | sed "s/[0-9\.]//g"`;
if [ "${checking}" != "" ]; 
           echo "Please type only numeric characters separated for dot";

2015-10-19 18:20:03

What Others Think

I like sed, but if you want a quick sanity check you can use bash's extended test syntax: [[ "$IP" =~ ^[0-9.]+$ ]] && echo OK || echo BAD
flatcap · 257 weeks and 3 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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