统计某个字符个数，小数运算，小数加减乘除

path=/abc/bdc/dsa/gafasd/casdf
计算字符'/'个数

echo -n $path | tr '/' '\n' | wc -l

echo -n $path | sed "s/[^/]//g" | wc -c

echo $[ ${#path} - `expr length ${path///}`]

 

小数运算

echo "scale=10;98512/258322" | bc