I\'ve been told it\'s a command line option. But Eclipse\'s Run!Run Configurations...!Target!Additional Emulator Command Line Options field is already occupied with
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Another useful addition to the above answers is filtering. The application I am working on generates a massive amount of logging, so it is useful to log with filters.
adb -s MyDevice logcat | find /V ": T#" > d:\temp\logcat.txt
or for OSX/Linux
adb -s MyDevice logcat | grep -v ": T#" > ~/logcat.txt
This will write all logcat activity apart from any line that contains ": T#"
find
or grep can also be used to filter based on positive results. I then use the likes of BareTail display the growing log file.