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Shell script breaks with grep

Sorry if this a basic/stupid question. I have no experience in shell scripting but am keen to learn and develop.

I want to create a script that reads a file, extracts an IP address from one line, extracts a port number from another line and sends them both toa a variable so I can telnet.

My file looks kinda like this;

Server_1_ip=192.168.1.1
Server_2_ip=192.168.1.2

Server_port=7777

I want to get the IP only of server_1 And the port.

What I have now is;

Cat file.txt | while read line; do
my_ip="(grep -oE '[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}' <<< "$line")"
echo "$my_ip"
done < file.txt

This works but how do I specify server_1_ip?

Next I did the same thing to find the port but somehow the port doesn't show, instead it shows "server_port" and not the number behind it

Do i need to cat twice or can I combine the searches? And why does it pass the IP to variable but not the port?

Many thanks in advance for any input.

Solution

  • Awk may be a better fit:

    awk -F"=" '$1=="Server_1_ip"{sip=$2}$1=="Server_port"{sport=$2}END{print sip, sport}' yourfile

    This awk says:

    1. Split each row into columns delimited by an equal sign: -F"="
    2. If the first column has the string "Server_1_ip" then store the value in the second column to awk variable sip: $1=="Server_1_ip"{sip=$2}
    3. If the first column as the string "Server_port" then store the value in the second column to awk variable sport: $1=="Server_port"{sport=$2}
    4. Once the entire file has been processed, then print out the value in the two variables: END{print sip, sport}