The VTTEST program tests the compliance to the VT100 standard of a terminal
or terminal emulator. It sends all sorts of devious sequences to the terminal
which will break many programs (screen corruption, crash, hang).
The full details can be found on
The VTTEST program itself can be downloaded from
If you want to run the test yourself, please make sure you first restore
full VT220 compatibility for IVT which is purposefully broken in the default
distribution to make it work best with most hosts out there...
Maximum VT220 compatibility can be set in IVT by choosing the "DEC-VT220" profile in
the "Create session" dialog.
The VTTEST score card from the Kermit project has a maximum score of 110
points - 100 for basic functionality tests, 10 bonus points for special
and extra features, some of which are not tested by VTTEST itself.
IVT scores 100 out of the basic 100, 10 out of 10 bonus points, for a
total score of a perfect 110!
To be honest, I added a bunch of VT52 features nobody ever missed,
just to satisfy VTTEST, this is the major difference between versions
14.1 and 14.1a.
A few vt-tests are noteworthy:
So, IVT scores 10 out of 10, making the total score 100 + 10 = 110.
It may sound proud but few other emulators get this far, not even the very expensive ones!
The VT220 engine in IVT is shared by all protocols (Telnet, Kerberized telnet,
SSH, Serial and Netbios, so it delivers the same accurate emulation
regardless of the type of connection.