Displaying all the logs from the default buffer on the Command Line can be accomplished by:
This command will show you all the logs from the device's main buffer. Notice that if you use it for the first time, you'll get a lot of information, an enormous stream of data. So you may want to clear the logs first...
Cleaning the logs:
adb logcat -c
This will clean clear the logs, and start fresh.
Displaying Alternate Buffers
There are two other buffers besides the main buffer that may be displayed as follows:
adb logcat -b buffer_name,
where buffer_name is one of the following:
radio- view the buffer that contains radio/telephony related messages.
events- view the buffer containing events-related messages.
main- view the main log buffer (default)
Filtering Log Output
Logcat logs got so called levels:
V — Verbose, D — Debug, I — Info, W — Warning, E — Error, F — Fatal, S — Silent
Those levels are specified when application uses those Log function:
Log.v(); // Verbose Log.d(); // Debug Log.i(); // Info Log.w(); // Warning Log.e(); // Error
if your code Log call is:
Log.i("MainActivtyTag", "Showing the very first fragment");
in logcat you'll see this output:
07-27 11:34:21.027 I MainActivtyTag 66 : Showing the very first fragment
So, this is the log convention:
<timestamp> <logLevel> <tag> <line> : <messge>
For instance, if you want to show all the logs that have Fatal (F) level:
adb logcat *:F
* is a what called a wild card - stands for all package names
Filtering by application package name
Since package names are guaranteed to be unique , you can filter logcat by your package name, of course you can combine it with the Level filter:
adb logcat <package name>:<log level>
For exiting/interrupting process - press
Ctrl + X