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I am using gsm-ussd to try and query my data balance from my 3G modem.

When I issue the commands

gsm-ussd -m /dev/ttyUSB0 '*188#'


gsm-ussd -m /dev/ttyUSB2 '*188#'

I get either "Device or resource busy" (when it is in used and connected) or "Unknown error (100)".

My device (Huawei E173) seems to create 3 devices in /dev, namely ttyUSB0, ttyUSB1 and ttyUSB2. None of them work, and ttyUSB1 gives a somewhat different problem, as it just give the following message:

* Wrong modem device (use -m <dev>)?
* Modem broken (no reaction to AT)

UPDATE I found the following post, but I am already doing what it says:

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Have a look on Vodaphone Mobile Connect for Linux. – BigSack Aug 9 '12 at 9:35

I have a Huawei E1780 which also creates /dev/ttyUSB0 , /dev/ttyUSB1 and /dev/ttyUSB2

gsm-ussd --device /dev/ttyUSB2 --no-cleartext '*100#'

works for me. You can also add --debug maybe that helps finding the problem.

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Welcome to Ask Ubuntu! This does not answer the question. – Ringtail Dec 9 '12 at 17:42
Uhhhm. You are right. Let me rephrase this: You may want to try adding --no-cleartext. I shared my personal experience since it seemed close to the OP's problem: a Huawei modem, that exposes three ttyUSB devices, and I got modem broken when I didn't use no-cleartext (maybe I should have mentioned that before) If I read it right, it is noted here that the program contains a list of modems that are known to require no-cleartext and for all non-known devices it does send it in clear text. Alternatively, look at (post) --debug – Jukke Dec 9 '12 at 20:13

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