Re: SYS$FAO coding example in BLISS-32

On 7/12/2024 1:17 AM, David Meyer wrote:

Jim Duff <jim@bad.invalid> writes:
         MSGDESC[0] = .RSLT;              ! Modify output descriptor
     ..............^
     %BLS32-W-TEXT, Fetch or store applied to field of zero size
     at line number 29 in file DISK$USER_01:[PAPA]SHOWTIMEUM.B32;2
 However, changing the flagged line as follows allows the example to
compile and run as expected:
      MSGDESC [DSC$W_LENGTH] = .RSLT;
 

In BLISS, structures are referenced by field selectors.
If you look at the definition of DSC$W_LENGTH in SYS$LIBRARY:STARLET.REQ, you'll see that it is:
macro DSC$W_LENGTH = 0,0,16,0 %;        !  A one-word field specifiec to the descriptor class;
The four field selectors are OFFSET, POSITION, WIDTH, SIGN.
Hunter