REXX function - MODIFY/STOP operator command for REXX programs.

Current build: 008

General information

 The program reads an outstanding modify or STOP command for the
 job. You may have up to 100 outstanding modifys before getting the
 'TASK BUSY' message. You can retrieve one modify as return value,
 or up to 100 modifys in a stem.

Syntax

 cc=RXOPCOMM('INIT'[,'wto-text'[,wto-opt]])

 Setup control blocks. INIT is not absolutely necessary as the GET
 will do an INIT if this hasn't been done. But it is good form to
 do INIT. See the WTO call below for details about the text and
 option.

 cc=RXOPCOMM('TERM'[,'wto-text'[,wto-opt]])

 Release control blocks TERM is not strictly necessary as the opsys
 will do cleanup after the job, but it good form to do TERM. See
 the WTO call below for details about the text and option.

 cc=RXOPCOMM('GET'[,'wto-text'[,wto-opt]])

 Check for response, return response text. Max response length is
 255. Optionally issue a WTO before check. See the WTO call below
 for details about the text and option.

 cc=RXOPCOMM('GETLIST',stemname[,'wto-text'[,wto-opt]])

 Returns outstanding MODIFYs in the named stem (which must end in a
 dot). 'stemname.0' holds the number of stem variables. The return
 code is 0 if no errors were encountered, even if no variables were
 set, but then 'stemname.0' is 0. See the WTO call below for
 details about the text and option.

 cc=RXOPCOMM('WTO','wto-text'[,wto-opt])

 Issue a WTO.
  Options:
  P  retains the text on the console permanently.
  J  retains the text on the console till the job ends.
 For WTOS with option J or P, descriptor code 11 'Critical Eventual
 Action Required' is used.

Return codes m.m.

 The program returns either
       - A text containing the modify text. The variable
         RXOPCOMM_MORE = 'Y' if more queued responses.
       - STOP if a P jobname was issued.
       - Blank if no modify was outstanding.
       - A error code plus an explanatory text in variable
         RXOPCOMM_REASON.

Samples

  cc=RXOPCOMM('INIT')
  if cc<>0 then exit 20
  cc=RXOPCOMM('WTO','OPCOMM initialization complete')
  wtotext='Enter command'
  Do $main=1 to 999 until rs='STOP'
    rs=RXOPCOMM('GET',wtotext)
    Select
      when datatype(cc)='NUM' & cc<>0 then do
        say 'RXOPCOMM error rc' rs RXOPCOMM_REASON
        exit 8
      end
      when rs='' then do
        wtotext=''
        call syscalls 'ON'         /* wait  */
        address syscall 'sleep' 2  /* 2     */
        call syscalls 'OFF'        /* secs  */
      end
      when rs='something-else' then do
      end
      Otherwise cc=RXOPCOMM('WTO','OPCOMM invalid command:' rs)
    end
  end
  cc=RXOPCOMM('TERM')
  cc=RXOPCOMM('WTO','OPCOMM ended')

  /* get all outstanding modyfys */
  do until RXOPCOMM_MORE<>'Y'
    rs=RXOPCOMM('GET')
  end

Members

 RXOPDOC      - this member
 RXOPCOMM     - install program
 RXOPIVP*     - installation verification / sample program
 SYSMACS      - local assembler macros used in the program

Installation notes

 RXOPCOMM is fully reentrant so can and should be in the LPA. If
 not, it will reload itself once to remain in the LPA - you can
 disable this behaviour by changing the JPAQ option at the top of
 the source.