sefran3 crashes when using fdsnws-dataselect and web server does not respond

The Sefran3 process crashes when doing a fdsnws-dataselect request while the remote web server providing the fdsnws service is not available.

This is the error from the stderr file :

WEBOBS{readdata}:  command unsuccessful [rc = 4]: chec: Connexion refuse.
Error in sefran3>readdata (line 597)
Error in sefran3 (line 205)

As one can see, this is due to the wget system call on line 597 of sefran3.m (in WebObs 2.1.2c) :
wosystem(sprintf('wget -nv -O %s "%s%s"',fmsdchan,datasource,wsreq),SEFRAN3);

I'm surprised that this wget error crashes the whole process. The expected behaviour would be to display an error message and continue with the realtime data plotting. A try/catch block would probably be useful here to catch the error without dying.

Start in sefran3.m at line 597 and trace the readdata path shown in the error. Inspect how wosystem reports the failed wget request, then verify that an unavailable fdsnws-dataselect server produces an error message while realtime data plotting continues instead of crashing sefran3.