What is the port listening command?

It is kind of a long story. The short version is that many people have been unnecessarily scared into spending a lot of money for security products that they don't need. If you have a wireless router or aren't running any servers on your Mac, then you don't need to block any incoming ports. You only need to block outgoing ports if you don't want your "legitimate" software to spy on you. There is just way too much security paranoia these days.

The long version is that you are 99.99% safe unless you do any of the following:
1) Use old versions of Windows
2) Use an unpatched version of Windows XP
3) Use Internet Explorer for Windows
4) Use Outlook for Windows
5) Do anything but delete unsolicited e-mail on Windows
6) Connect directly to the Internet instead of using a $10 hardware router such as a wireless router.
7) Run servers such as web servers or peer-2-peer software.

If you aren't doing anything on this list, you will be fine. Yes, there is still an extremely small risk, but that risk is virtually non-existent. You will never get to 100% safe. Trying to get from 99.99% safe to 99.9999999% will cost a lot of money, waste a lot of time, and make your computer virtually useless.

Just turn off everything in "Sharing" and you'll fine. No extra software needed. If you are really paranoid, download and buy Little Snitch for $25. It has a much better rating and is much more popular than Netbarrier

netstat -a (from Terminal). Experience with sockets programming will be helpful when interpreting the output.

look on Macupdate.com or Versiontracker.com and get NMapFE a GUI front end for NMap. You run it from a different computer than the one you are scanning. I don't know if nMap is built-in enabled in the Mac or not, I can't remember how/where I got NMap up and running, whether it came with nMapFE, whether I got it from Fink, sourceforge.net, or what.

One variation of the longhand command would be nMap -sT -p {port list} -T{1-5, 1 slowest 5 fastest} {IP address of target computer}. Port list is like "0-65535" or "7000,8444,9000-90002"

Or, launch Network Utility in your (other computer's) /Applications/Utilities folder and go to the Port Scan panel. As with nMapFE, you really need to run this from a different computer than the one whose ports you are trying to scan.

However you accomplish it, be prepared to give 0-65535 a weekend to do it, though.



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Because "a web browser that uses port 80" isn't what you think it is. Port 80 is the default port for web servers; so the web browser on your system is connecting to port 80 on the server's system.

It would be rare for a browser to use port 80 on its own machine, and extremely rare for a UNIX-based system. Most non-server applications don't specify a particular port when they open local sockets; the O/S randomly assigns them one above 1000.

However, if you were to enable Personal Web Sharing, netstat should show that port 80 is LISTENING; that would be your Apache web server.

The "connection" for a web browser is only open long enough to retreive the data displayed in the browser window. Usually, this is just a second or so - often less than a second for many sites. You might see open ports if you almost simultaneously click a web link and execute a netstat -a command.

Well, there's always the netstat(1) man page... ("man netstat" in Terminal.)

just because at one point you asked.

assuming tcp:
sudo lsof -i tcp:7000
sudo lsof -i tcp:8444

or you can just run

sudo lsof -i :7000

Andy

yes, if lsof doesn't find a process attached to that port. nothing but the prompt is returned.

another way of listing the all open inet or AF_INET ports is with netstat.

netstat -anf inet

but this will not tell you the process id.

You would be better off posting a new thread; hijacking someone else's thread usually won't get the attention of the right people. Usually.

In this case, I can say that that is the difference between an admin user and a non-admin user; admin users can sudo. Remember that "sudo" means "do as super-user"; it assigns the process executing the target command "root" privileges. This is powerful and potentially dangerous (e.g., "sudo rm -rf /". Don't do that. Just don't.). Users to whom you want to provide such power should be administrators.

Powerbook G4 1GHz Mac OS X (10.3.9)