.FL CAPITALIZE
.PS 60,72
.LM 8
.RM 72
.P 4,1
.AP
.S 2
.c ;RASM MODIFICATIONS
.s  3
The program which actually delivers the plot information to the 
device runs as a subprocess under VQ. Communication between
VQ and the subprocess is via mailboxes, and must adhere to a
rigid protocol; failure to do so results in loss of synch, and
you must restart everything to get going again.
.s
The program usually run in the subprocess is a slightly modified
RASM, but if you are willing to make some mods to QRX and VQ, you
can run anything you want there.
.s
The standard protocol is:
.ls
.le
VQ delivers three lines of information to the subprocess. They
contain, respectively, the name of the parameter file, the name
of the vector file, and the name of the device to which the plot
is directed.
.le
VQ expects one, AND ONLY ONE, line to be returned from the
subprocess. In FORTRAN terms, the data returned is the completion
code, the CPU time used in seconds, and the number of direct IOs,
in (' DONE ', i2, 1x, i4, 1x, i6) format. If accounting is turned
off, the CPU time and IOs need not be supplied.
.le
It is vital that all error printout statements be removed, and
replaced with code which sets the completion code. Cluttering the
mailbox with any kind of output other than the line described above
will cause failure.
.els
.s
I am using the Rev B VERSATEC RASM routine, for which the required
modifications are as follows:
.s 
.ls
.le
Vanilla RASM assumes that the files to be plotted are
PARM.PLV and VECTR1.PLV, in the current default directory.
I have modified IOPKG.MAR to open PARM_FILE and VECT_FILE;
RASM reads in the actual file names and attaches the above
logical names to them.
.le
Vanilla RASM allocates the device "_LV:". From the presence
of the colon, I assume that they meant for this to be a logical
name; if so, I don't understand the underscore. In any event,
the device name must be read in by the main program, and the logical
name "LV:" attached to it. Further, the allocate must be removed
from MTX.MAR; the spooler allocates (and KEEPS) the plot device.
.le
Standard RASM puts out a bunch of messages about
lines used, vectors used, and so forth; these have been
eliminated in favor of a single line at the end.
.els 
 RASM inputs three lines: one is the PARM file name, two is the
VECTR1 file name, and three is the device name. It outputs one
line only, which contains a status code. The code is
.s 
.lit
       0 ==> successful completion
       1 ==> paramter/file mismatch (bad input file)
       3 ==> INBUF array improperly dimensioned
       4 ==> Map buffers exceeded
.end lit
.pg
.c ;CODE MODIFICATIONS
.s 
.c ;RASM
.s 
At the beginning of the main program RASM, 
insert the following declaratives:
.s 
.lit
		INTEGER STAT, SYSMSG, SYS$CRELOG, ERROR, PFLEN, VFLEN
                INTEGER CPU, DIO
                CHARACTER*48  PFILE, VFILE, LVNAME
.end lit
.s 
Then remove the
format statements numbered 1, 2, 3, 4, 6. Insert the
following:
.s 
.LIT
		ACCEPT 10, PFLEN, PFILE
	10	FORMAT( Q, A )
		ACCEPT 10, VFLEN, VFILE
		ACCEPT 10, LVLEN, LVNAME
	C
		STAT = SYSMSG(SYS$CRELOG(%VAL(2), 'PARM_FILE',
		1 PFILE(1:PFLEN), ) )
	C
		STAT = SYSMSG(SYS$CRELOG(%VAL(2), 'VECT_FILE',
		1 VFILE(1:VFLEN), ) )
	C
		STAT = SYSMSG(SYS$CRELOG(%VAL(2), 'LV',
		1 LVNAME(1:LVLEN), ) )
	C
		ERROR = 0
.end lit
.s 
Next, modify all TYPE statements in RASM: change
.s  
.lit
          TYPE n

            to

          ERROR = n
          GO TO 7899
.end lit
.s  
Delete entirely the line
.s 
.lit
          TYPE 6, LOST, MAXQ
.end lit
.s 
At the end of the main program, replace the line
.s 
.lit
          STOP '** End of RASM **'

                 with

          CALL RXSTAT ( CPU, DIO )
          CPU = (CPU+50) / 100
          PRINT 8000, ERROR, CPU, DIO
     8000 FORMAT(' DONE ', I2, 1X, I4, 1X, I6)
          CALL EXIT
.end lit
.pg
.s  4
.c ;IOPKG.MAR
.s 
Modify both FAB's to accept logical names.
.s 
.lit
            Change

                PARM_FAB:
                        $FAB    FNA=PARM_NAME, -
                                FNS=PARM_NAME_SIZ, -

            to

                PARM_FAB:
                        $FAB    FNM=<PARM_FILE:>, -

            And change

                VECTR1_FAB:
                        $FAB    FAB=VECTR1_NAME, -
                                FNS=VECTR1_NAME_SIZ, -

            to

                VECTR1_FAB:
                        $FAB    FNM=<VECT_FILE:>, -
.end lit
.pg
.s  2
.c ;MTX.MAR
.s 
.LIT
	Change

	LV_DESC:   \_LV:\

	to	

	LV_DESC:   \LV\
.END LIT
.s 
The section of code beginning with
.LIT

	10$:    $ALLOC_S   DEVNAM=LV_DESC

        and ending with the line JUST BEFORE

	25$:    $ASSIGN_S  DEVNAM=LV_DESC -
			   CHAN=LVCHAN
.END LIT
.s 
must be removed. This is the code which allocates the device,
and waits until it gets it. RASMX runs as a sub-process
to VQ, and VQ owns the device permanently.