sim: try "ON" phonebook entry #1 if AT+CNUM fails
Submitted by Aleksander Morgado
Assigned to ModemManager bug user
Originally reported at: https://bugzilla.gnome.org/show_bug.cgi?id=696693
Some devices always reply with ERROR to AT+CNUM, but switching to the own-numbers (ON) phonebook and checking entry #1 shows the correct number.
at+cnum? ERROR at+cpbs="ON" OK at+cpbr=1 +CPBR: 1,"16121234567",129,"004D0073006900730064006E0031" OK
Yes, the modem is in UCS-2 character set and the UCS-2 string spells "Msisdn1". If other SIMs have "Msisdn1" here too, maybe we could use that as a check.
Another possibility would be to directly read from a SIM file through +CRSM.