Re:

> BUILD MSTEST;MSG;REC=-1000,,V,ASCII;DISC=10000
>
> that MPE pads your variable length writes to the file with spaces (or binary
> zeros if the file is defined as Binary rather than ascii) - effectively making
> this a fixed length file of 1000 bytes !

No, it doesn't do such padding.

Proof:

   :BUILD MSTEST;MSG;REC=-1000,,V,ASCII;DISC=10000
   :fcopy from=;to=mstest

   HP31900A.05.02 FILE COPIER (C) HEWLETT-PACKARD CO. 1990

   *200*WARNING: FROMFILE RECSIZE IS 80 BYTES, TOFILE RECSIZE IS 1000 BYTES.
   CONTINUE OPERATION (Y OR N) ? Y
   short
   longggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggg
    < CONTROL Y >

   2 RECORDS PROCESSED *** 0 ERRORS

   End Run
   :debug
   DEBUG/iX C.16.01

   $1 ($58) nmdebug > map mstest
   1  MSTEST.SOURCE.SIELER   950.0 Bytes = 98b1d8
   $2 ($58) nmdebug > dv 95.0, 20,s, e
   VIRT $950.0        "..short .Plonggggggggggggggggggggggggggggggggggggggggggg"
   VIRT $950.38       "gggggggggggggggggggggggggggg  ...
   $3 ($58) nmdebug > unmap 1

What you may be seeing is that when you READ the message file,
records are padded to the file's record size.

   :fcopy from=mstest;to=;hex

   MSTEST RECORD 0 (%0, #0)

   0000: 7368 6F72 7420 2020 2020 2020 2020 2020 2020 2020 2020 2020
   000C: SAME: TO 01F4-1

   MSTEST RECORD 1 (%1, #1)

   0000: 6C6F 6E67 6767 6767 6767 6767 6767 6767 6767 6767 6767 6767
   000C: SAME: TO 0018-1
   0018: 6767 6767 6767 6767 6767 6767 6767 6720 2020 2020 2020 2020
   0024: SAME: TO 01F4-1
   EOF FOUND IN FROMFILE AFTER RECORD 1

Both records came from the file as though they're $1f4 halfwords long
($1f4 * 2 = #1000 bytes)

Stan




Stan Sieler                                           [log in to unmask]
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