How to restart the modem on Arch

[lacriz]

If you find an indicator for a non working modem that can be checked by code, you could for example also have the script check it

I tried to do that from my bash script but no success so far:

Code:

sudo [ -d "/dev/ttyUSB2" ] echo "modem works" || "modem no worky"

This results in "modem no worky" even though:
1) it actually works
2) I can see that device e.g. using ls /dev/ttyUSB2

So now I have 2 more questions to be able to automate the whole workaround on Arch:
1) How can I find out which device in /dev is actually representing my eg25 modem? (I could not see any such path mentioned in ModemManager's output and also no command when entering ModemManager -h)
2) How can I check in bash if a /dev/BLABLA path exists / is working?

Cheers

  lacriz