finding which program produces a log file

I am using Ubuntu 15.10 and I have an email account configured on the terminal. Probably a left-over from the time I tried to configure that account, I have some logs being printed to a file in my home directory a couple of times day. An example of a log (one line, split here for readability): 28 12:36:02 host=smtp.gmail.com tls=on auth=on user=***@gmail.com from=***@gmail.com recipients=&&& smtpstatus=553 smtpmsg='553 5.1.2 The recipient address is not a valid RFC-5321 address. q65sm28155223wmd.6 - gsmtp' errormsg='recipient address &&& not accepted by the server' exitcode=EX_DATAERR It is printed to ~/msmtp.log My question is how can I discover where does this printing comes from in order to kill it? Solution: The log was printed by msmtp itself. A quick look at the msmtp manfile showed that the configuration file is ~/.msmtprc . I edited this file to change the log file.