In exec.sh line 1:
    if [ exec 1>/dev/null 2>/dev/null 3>/dev/tcp/localhost/4000 ] ; then
    ^-- SC1009: The mentioned syntax error was in this if expression.
       ^-- SC1073: Couldn't parse this test expression. Fix to allow more checks.
         ^-- SC1014: Use 'if cmd; then ..' to check exit code, or 'if [[ $(cmd) == .. ]]' to check output.
              ^-- SC1072: Expected test to end here (don't wrap commands in []/[[]]). Fix any mentioned problems and try again.
    
    For more information:
      https://www.shellcheck.net/wiki/SC1014 -- Use 'if cmd; then ..' to check ex...
      https://www.shellcheck.net/wiki/SC1072 -- Expected test to end here (don't ...
      https://www.shellcheck.net/wiki/SC1073 -- Couldn't parse this test expressi...