Checking for MySQL access

[Devin Asay]

Hi all,

I recently had to demonstrate one of my apps at a conference at  
another university. The app accesses my MySQL server at home, but over  
a non-standard port (i.e., not 3306). The conference hosts provided a  
temporary login to get onto the institution's WiFi network. During my  
demo I was baffled to discover that some people could use my app just  
fine, while others on the same network encountered a long hang while  
the app attempted to access my MySQL server, culminating in a failure  
and error message about an invalid MySQL connection id.

Eventually, I discovered that there were two different accounts that  
we could use to access the network. The first, the temporary account,  
gave conference participants relatively unrestricted access, but the  
other, a 'guest' account, gave much more limited access. Relevant to  
this issue, the guest access apparently had a more restrictive  
firewall that blocked the port I needed.

So this brings up a question. How could I check any given network to  
make sure that the appropriate ports is open BEFORE committing to  
attempting a MySQL connection, which seems to take about 2 minutes  
before it times out. I'm working on OS X, but would need a cross  
platform solution. Would some kind of netstat shell call give me the  
information I need?

Regards,

Devin