包含 ip 地址的变量的算术

Question

我有变量

network="198.168.1.x"  # for ex. 198.168.1.254

我想创建新变量：

next_serv="198.168.1.(x-1)"  # for ex. 198.168.1.253
max_host="198.168.1.(x-2)"   # for ex. 198.168.1.252

怎么做？

Answer 1

network="198.168.1.254"
IFS="." read -r a b c d <<< "$network"
next_serv="$a.$b.$c.$(($d-1))"
echo "$next_serv"

输出：

198.168.1.253