is there a function to know if a variable is a number 1

[cantubas]

is there a function to know if a variable is a number or no ???

to know if a variable is a number I do:
if (( parametres = $parametres + 0 ))
then
echo "it's a number"
else
echo "it is not a number"
fi

... does another solution exist?

 

[aigles]

With ksh, you can do :

if [[ "$parametres" = +([0-9]) ]]
   then  echo "it's a number"
   else  echo "it is not a number"
fi

Jean Pierre.

 

[SamBones]

In the Korn shell you can force a variable to only accept numeric characters...

typeset -i parametres

From that point on, it will only accept integer values.

Hope this helps.