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2.0;siomonit (sio_process_monitor), revision 2.0, 83/10/07
SIOMONIT (SIO_PROCESS_MONITOR) --
usage:  SIOMONIT filename [-monit]


  SIOMONIT   supports  repeated  logins  over  sio  lines,  independent  of  any
  login/logout activity at the node terminal.    The  file,  filename,  contains
  argument lists to be passed to invocations of siologin (see the description of
  SIOLOGIN  for  more  information).  A maximum of three argument lists (one per
  sio line) are processed.  SIOMONIT must be  invoked  as  a  server  (CPS)  and
  SIOLOGIN  must be a manager within the LOGIN protected subsystem for the login
  procedure to be successful (cf: siologin.hlp).

  Each argument list in the file must have the form:

    [-Repeat]  siologin_arg_list

  where
    -Repeat               means re-invoke this process each time it returns.
    siologin_arg_list     is an siologin argument list of the form:
                  /DEV/SIOx  [[-dialin]  [-n processname]  prog [ args ...]]

  For each argument list, SIOMONIT invokes:

    /sys/siologin/siologin  siologin_arg_list


  Arguments are passed to SIOLOGIN unvalidated except that the first one must be
  /dev/siox, specifying the sio line to use.  If the invocation fails, or  if  a
  process  returns  from its invocation within 15 seconds, SIOMONIT will wait 15
  minutes before attempting to start the process again.  SIOMONIT  re-reads  the
  argument file each time a child process dies.  An asynchronous quit fault will
  cause  SIOMONIT  to re-read the argument file and try to restart processes for
  unused lines.  A stop fault causes SIOMONIT to exit.  (Processes that  do  not
  have  the  -repeat argument are given only one successful start per reading of
  the input file.)  The SIGP command may be used to send stop and  quit  signals
  to SIOMONIT.

  A  frequent  cause of failure of an SIOLOGIN process to stay alive is a locked
  sio line (/DEV/SIOx).  If you free up a line, use SIGP to prod  SIOMONIT  into
  trying  again.    If  you add entries to the argument list file, you must SIGP
  siomonit (or you may cause a child process to die).  If you change  or  delete
  an  entry  in  the  argument  file,  it will take effect only when the current
  process for that sioline dies.  You may usually kill an siologin process  with
  SIGP.

  If  SIOMONIT  is  stopped (sigp -s) while any of its child processes are still
  alive, if it is reinvoked it will not recognize the death  of  an  old  child.
  However if the name of an old child (-n option to SIOLOGIN) is the same as the
  name  in  the  command  list for that sioline, it will reinvoke the process on
  that line within 15 minutes of when the old child dies.

  SIOMONIT writes a log of  certain  events  in  `node_data/siomonit_log.    The
  -MONIT  option  causes SIOMONIT to also dump its tables each time it writes to
  the siomonit_log.  The log gets large and should be editted periodically.

  Comments may be included in the SIOMONIT file and must begin with #.

Typewritten Software • bear@typewritten.org • Edmonds, WA 98026