Why is the following expression giving me a expr: syntax error?
pingval=`expr ping6 -c 1 "$url"`
Basically I want to use the value returned by the above expression in another expression eg
var=$($pingval|tail -1 ....
Any suggestions?
Why are you using expr
at all? It's generally used for simple maths / string functions.
You can assign the result (stdout) of that expression just using the backticks, or in a more modern way directly with:
pingval=$(ping6 -c1 "$url" | tail -1)
If you did want to build the shell expression before using, try something like:
cmd="ping6 -c 1 '$url' | tail -1"
echo cmd | sh
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