How to handle exceptions right?

[dog2002]

I want to call functions according to an exception. In C there is 
the errno function. But if I use try...catch, it shows a trace or 
a message. How do I check an exception type? For example:

std.socket.SocketOSException at std/socket.d(2857): Unable to 
connect socket: Connection refused
----------------
??:? [0x459ec5]
??:? [0x4646e6]
??:? [0x44743d]
??:? [0x42c833]
??:? [0x404273]
??:? [0x404cf8]
??:? [0x440a43]
??:? [0x7fdeccecc3f8]
??:? clone [0x7fdeccc98b52]

or

Unable to connect socket: Connection refused

So do I just need to check the exception string? Or there is 
something like errno in C?