If you want to cancel a job, you can remove it from the queue using faxrm:
% faxstat -s HylaFAX scheduler on tove.cs.umd.edu: Running Modem cua/a (+1 301 405 6707): Running and idle JID Pri S Owner Number Pages Dials TTS Status 20 127 R bplecs 93014056707 0:0 0:12 % faxrm 20 Job 20 removed.
Note that the argument to faxrm is the job ID, or the JID listed in the output of faxstat -s. The job ID is also reported to you as the 'request id' when you run sendfax. These are the same number:
% sendfax -d 93014056707 /tmp/paper.ps request id is 20 (group id 20) for host fax.cs.umd.edu (1 file)