Where does RACK log to?

Question

I am running a sinatra app through RACK.

To which file does the activity get logged ? Also how can I set the log file path ?

Answer 1

The object_id are initially the same but it's better to assign to $stderr. That also leaves you open to return the stream to where it was originally with STDERR:

 $ irb
>> $stderr.object_id == STDERR.object_id
=> true

Same object, for now. Send it elsewhere,

>> $stderr = File.open('/tmp/foo', 'w')
=> #
>> $stderr.puts "Uh-oh, foo"
=> nil
>> $stderr.flush    # if you want to verify its output
=> #
>> $stderr.object_id == STDERR.object_id
=> false

$stderr and STDERR refer to different objects. STDERR still streams to the terminal here,

>> STDERR.puts "Uh-oh, original STDERR"
Uh-oh, original STDERR
=> nil

Restore $stderr,

>> $stderr = STDERR
=> #
>> $stderr.object_id == STDERR.object_id
=> true

And we're back!