IFS read in loop bash-CodePudding

I would like to iterate on a loop, my variable $_INFO on which I loop contains:

tcp/443
tcp/80
udp/54

I tried to parse my variable with this loop

_INFO=("tcp/443" "tcp/80" "udp/54")
for val in "$_INFO"; do
   IFS=/ read _PROTOCOL _PORT <<< $_INFO
   echo "protocol: $_PROTOCOL"
   echo "port: $_PORT"
done

I receive in output :

protocol: tcp
port: 443 tcp/80 udp/54

While I would like to receive in output:

protocol: tcp
port: 443
protocol: tcp
port: 80
protocol: udp
port: 54

Any pointers in the right direction would be of help. Thanks

CodePudding user response：

If awk is ok:

$ echo "$_INFO" | awk -F\/ '{printf "protocol: %s\nport: %d\n", $1, $2}'
protocol: tcp
port: 443
protocol: tcp
port: 80
protocol: udp
port: 54

CodePudding user response：

bash alone is enough, thanks to parameter expansion with removal of matching prefix or suffix pattern:

_INFO=("tcp/443" "tcp/80" "udp/54")
for val in "${_INFO[@]}"; do
  echo "protocol: ${val%/*}"
  echo "port: ${val#*/}"
done

CodePudding user response：

You have to feed the whole loop with your input.

#! /bin/bash

_INFO='tcp/443
tcp/80
udp/54'

while IFS=/ read _PROTOCOL _PORT; do
  echo "protocol: $_PROTOCOL"
  echo "port: $_PORT"
done <<< $_INFO