Use fuser to display the process IDs using local TCP port 443.
Do not terminate any process.
Which command is appropriate?
fuser PORT/tcp displays processes using the specified TCP port. Adding -k would send a signal and is not appropriate for read-only auditing.
Detailed explanation
fuser -k 443/tcpIncorrect. -k sends a signal to the matching process and can terminate it.
Incorrect. -k sends a signal to the matching process and can terminate it.
fuser 443/udpIncorrect. It targets UDP port 443.
Incorrect. It targets UDP port 443.
fuser 443/tcpCorrect. It displays processes using TCP port 443.
Correct. It displays processes using TCP port 443.
fuser tcp/443Incorrect. The port and protocol order is not the normal fuser form.
Incorrect. The port and protocol order is not the normal fuser form.
Try it yourself
An example you can run in a temporary verification environment.
printf '%s
' '443/tcp=TCP port 443' '-k=kill matching processes'Expected result
443/tcp=TCP port 443
-k=kill matching processesKey points
- Use PORT/protocol form
- Display the PID
- -k changes state
Notes
- Environment: psmisc fuserの構文対応表
- Command output formatting can vary slightly by distribution or tool version.
- Run the example in a temporary directory or process when possible.
Foundation review
Read the scope first
Check whether the command acts on the current shell, a new process, an existing process, or a file.
Verify the observable result
Use the supplied command and compare the output with the expected result.