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1) HOW TO USE ZOCEVENT.ZRX
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   The ZOCEVENT.ZRX file is called at certain points in ZOC (with the
   parameters identifying the event shown in the table below).

   The ZOCEVENT file can, for example, be used to turn off a fax program
   before ZOC will try to access the com port and turn fax receive mode 
   back on when ZOC exits (OS/2's FaxWorks offers such a feature via the
   FXRCV.EXE program, as shown in the sample ZOCEVENT.ZRX file).



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2) CALL PARAMETERS
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   ----------------------------  ------------------------------------------
   EVENT                         PARAMETER(S)
   ----------------------------  ------------------------------------------
   ZOC Start                     OPEN
   Before a device is opened     DEVOPEN '<device name>' '<device opts>'
   After a device was closed     DEVCLOSE '<device name>' 
   ZOC Ends                      CLOSE
   ----------------------------  ------------------------------------------

   The DeviceName is the same as it appears in ZOC, but always in upper
   case letters (eg. SERIAL/MODEM).

   The DeviceOpts are undocumented, so you need a bit of experimenting
   with them (see the debugging section below).  However, since they are 
   probably only used to determine the com port, here is how to parse 
   the SERIAL/MODEM options:

   /* ZOCEVENT.ZRX */
   PARSE ARG Event " '" DeviceName "'" "'" DeviceOpts "'"

   /* if serial, get com port */
   IF Event="DEVOPEN" & DeviceName="SERIAL/MODEM" THEN DO
       PARSE VALUE DeviceOpts WITH "[" id "]" serport ":" baud "-" opts "|" 
       serport= TRANSLATE(serport)  /* uppercase */
       CALL LINEOUT "zocevent.trc", "OPEN OF "serport" DETECTED"
   END /* IF */



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3) SPECIAL PROGRAMMING ISSUES
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   You can call all of the ZOC commands.  However, not many will make
   sense in the environment in which ZOCEVENT.ZRX is called, because
   no communication device is open and (in case of OPEN and CLOSE) not
   even a ZOC window is there.



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4) DEBUGGING
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   If no ZOC window is there, SAY or TRACE will pop up a message window
   with the message you want to show.  As this makes debugging a bit
   tedious, you can write debugging output to a file with REXX's 
   lineout command:

      CALL LINEOUT "zocevent.trc", event "#" DeviceName "#" DeviceOpts

   Under OS/2 you can call the script from the command line with the 
   same parameters that ZOC would use, eg.:

      C:\ZOC> SCRIPT\ZOCEVENT "DEVOPEN" "SERIAL/MODEM" "[1]COM3:38400-8N1|"