How to disable the replica set monitor output

Question

I have a bash script which tries to monitor the number of documents in a collection by connecting to a replica set.

COUNT=`/bin/mongo --quiet --host $REPLICA_SET policy -u myuser -p mypwd --eval 'db.myColl.count()'`

I was expecting only a number as output, however I got:

Mon Apr 27 13:33:57.716 starting new replica set monitor for replica set xx wit                                                                             h seed of xxx 
Mon Apr 27 13:33:57.719 succes                                                                             sfully connected to seed xx for replica set xx
Mon Apr 27 13:33:57.719 changing hosts to ...  

...

Mon Apr 27 13:33:57.736 [ReplicaSetMonitorWatcher] starting 3043

Could anyone tell me how to disable this bunch of output? Thank you.

Answer 1

I could not figure how to disable this. As a workaround you could a) tail -1 your output, or b) output a token that's likely to be unique just before your output and then grep it (e.g. in js: print("__myAwesomeOutput__=" + x + ";").