1 printf 'a\t\tb\tc\n' | ( IFS=$(printf "\t") read a b c; echo ".$a. .$b. .$c." )
2 printf 'a\t\tb\tc\n' | ( IFS=$(printf " \t") read a b c; echo ".$a. .$b. .$c." )
3 printf 'a,,b,c\n' | ( IFS="," read a b c; echo ".$a. .$b. .$c." )
4 printf 'a,,b,c\n' | ( IFS=" ," read a b c; echo ".$a. .$b. .$c." )
5 printf 'a ,, c\n' | ( IFS=" ," read a b c; echo ".$a. .$b. .$c." )
6 printf 'a ,, c d\n' | ( IFS=" ," read a b c d; echo ".$a. .$b. .$c. .$d." )
7 printf ' a,,b,c,d , ,\n' | ( IFS=" ," read a b c; echo ".$a. .$b. .$c." )