Hi Marek, On Sun, 1 Nov 2020 at 16:08, Marek Behun <marek.behun at nic.cz> wrote: > > What is the purpose of + operator on strings? > Can't we use setenv "${a}${b}" ? Yes, that does the same thing, although it is a bit clumsy. setenv a *10 setenv b *100 setenv c "${a}${b}" instead of setexpr c *10 + *100 Regards, Simon