Use _ to shorten tag names instead of *.

[lhunath]

A common method of enabling logging for a certain tag involves issuing the setprop command via adb shell. Unfortunately, it is impossible to set a property on a key whose name contains a * using this method. As such, * is a bad choice for shortening tag names, since it means we cannot use this method for setting the log level of a tag.

[mattbishop]

Can you point to some android docs that describe this convention?