So this is an old old script I wrote from years ago. This enables you to enter commands into a multicraft console and tail the log file. I don't know if it still works, I updated it and added -r to the "read"'s as well as double quotes around variables. All should still be well.

MulticraftConsoleViaBash.sh

#!/bin/bash

### https://pastebin.com/4pVGcwQE

if [ -t 0 ]; then stty sane; fi
if [ "$(whoami)" != "root" ]; then echo "This needs to be run as root!" ; exit 0 ; fi
echo -n "Username: "; read -r -t 15 username_
ps -au "$username_" ; echo "--------------------------------------------------"
echo -n "PID: "; read -r -t 15 PID_
userhome=$(eval echo "~$username_")
OldLine=""
keypress=""
if [[ -f $userhome/logs/latest.log ]]; then
        logFile="$userhome/logs/latest.log"
elif [[ -f $userhome/server.log ]]; then
        logFile="$userhome/server.log"
else
        if [ -t 0 ]; then stty sane; fi
        echo "NO LOG FILE FOUND."
        echo "Exiting."
        exit 0
fi
while true; do
        if [ -t 0 ]; then stty echo -icanon time 0 min 0; fi
        keypress=''
        while [ "x$keypress" = "x" ]; do
                newLine=$(tail -n 1 "$logFile")
                if [ "$OldLine" != "$newLine" ]; then
                        OldLine=$newLine
                        echo "$newLine"
                else
                        OldLine="$newLine"
                fi
                read -r keypress
        done
        if [[ $keypress = "z" ]]; then
                if [ -t 0 ]; then stty sane; fi
                echo -ne "\rExiting.\n"
                exit 1;
        fi
        if [ -t 0 ]; then stty sane; fi
        echo -en "\rPress z to exit.\n"
        echo -en "Enter Command>"
        read -r lol
        echo "$lol" > "/proc/$PID_/fd/0"
        echo -en "\033[1A\033[2K\r>$lol\n"
done
function finish { if [ -t 0 ]; then stty sane; fi }
trap finish EXIT