Re: Adding pre/post escape sequences to a "SAY"

JF Mezei wrote:

$SAY = "WRITE SYS$OUTPUT" exists on pretty much every VMS system, in many
procedures.

However, what I would like to be able to do is to have a SAY that insert
escape sequence before the message, and another escape sequence after the
message.

(for instance, in a scrolling region environment of a VT terminal, have the
SAY cause the message to be written to the top window, and then return to
the bottom window for any other output).

The one thing I could think of is to define a subroutine:

$SAY: subroutine
$write sys$output esc1,p1,esc2
$exit
$endsubroutine

and then in the program, use CALL SAY "This is the message"

Are there any other suggestions on how this could be done efficiently ?

However, one big drawback of this is that CALL SAY is quite different from
WRITE SYS$OUTPOUT in terms of how the arguments are handled.

one can do WRITE SYS$OUTPUT symbol1,symbol2,symbol3
but you can't CALL SAY symbol1,symbol2,symbol3

Well, technically, you can. Here's how it would work:

$SAY: SUBROUTINE
$ write sys$output esc_seq_1,'p1',esc_seq_2
$ exit
$ endsubroutine

Actually, what I would recommend is this:

$ say := call show_text
.
.
.
$ SAY symbol1,symbol2,symbol3
.
.
.
$ exit
$!
$show_text: SUBROUTINE
$ write sys$output esc_seq_1,'p1',esc_seq_2
$ exit
$ endsubroutine


Any way around that would give me the exact same functionality that is
available with WRITE ?

Well, with the caveat of embedded quotes, that's almost plug-and-pray.

Also, is it correct to state that when using:
$CALL SAY "Nodename: ''f$getsyi("SCSNODENAME")'"

That the argument passed to SAY will have already been expanded (eg: any
symbols inside the strings are translated before it enters the subroutine ?)

Absolutely.

--
David J Dachtera
dba DJE Systems
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