Pbox Events set by calling server with 'event n c' where n is line number, and
c is + or - a letter, eg 'event 1 +M' sets the 'message entered' event for
line 1.

 L      Linedrop or timeout, used by Linetidy updating 'drops' counter
 M      Message(s) entered, used by Linetidy and Tossmail
 U      File(s) uploaded, used by Linetidy and Topten
 D      File(s) downloaded, used by Linetidy and Topten
 F      Faxmail message entered. Used by faxmail_prg
 E      Echomail or netmail received
 R      Caller has read all his new mail
 Q      Caller has answered the questionnaire
 B      ringBack requested

All events activate a program whose name is looked up from system_dat in the
form EVENTn_PRG. Special action is taken within Linetidy for events LMUDERB.
You may still set EVENTn_PRG for these letters if you wish to take additional
action. Within Linetidy, U or D cause Topten_prg to run, and L,M,U,D all
increase the relevant settings in users_dbs. F causes the bbs line to be
killed, Faxmail_prg run, then the bbs line is restarted. E processes inbound
mail and then calls scanmail to pass the mail on to other feeds.
R deletes the users 'newmail' file.

All external event programs are run with a command line of the line number,
and if "quiet" is set, #0 is redirected to 'nul'

Linetidy also handles events in an event file. Currently supported events
are....

FDn             File Download
                Increase the 'no of downloads' entry in files_dbs for
                recnum n

FUa n d          File upload. a = area number, n = filename, d = description
                 which may contain spaces. This creates a 'files_dbs' entry.

MRa n           Message Read
                Flag message with msgid n in area nr a as having been read by
                it's intended recipient. Note: n is remainder of line and may
                contain spaces.

MDa n           Message Delete
                Delete message with msgid n in area nr a. Note: n is remainder
                of line and may contain spaces.

MUa n           Message Undelete
                Remove deletion flag for  message with msgid n in area nr a.
                Note: n is remainder of line and may contain spaces.

UNa             User Name
                All actions in the event file from this point on were carried
                out by this named user

MLa             Mailer
                All actions in the event file from this point were carried
                out by this mail caller

EVa             EVent list
                At the end of a call, these were the event letters triggered

RBn             ringback request, call this number

FRa n           File Removed (deleted), area a, name n. Remove files_dbs entry
                and rebuild the file list

FFa n           File Freq for name n in file area a. Increase "download" count
                for the file. Area = - if name is magic
