[Info-vax] Local Versus Global Command Options

[Arne Vajhøj]

On 2/13/2025 5:52 PM, Lawrence D'Oliveiro wrote:
> What would DCL-style syntax for ffmpeg look like? I suppose one
> obvious equivalence would be
> 
>      ffmpeg -
>          «infile-1»/«local-input-options-1»,«infile-2»/«local-input-options-2»,... -
>          «outfile-1»/«local-output-options-1»,«outfile-2»/«local-output-options-2»,... -
> 
> (being very careful about where the commas go), but what about the
> syntax for filtergraphs? Would it be something like
> 
>      /vf=(«filter-name-1»=«filter-params-1»,«filter-name-2»=«filter-params-2»...)
> 
> Does DCL have provision for this sort of complexity?

You can do quite a bit with CDU, CLD and CLI$:

$ type fun.cld
define verb fun
     image "sys$disk:[]fun"
     parameter p1, value(type=$file)
     parameter p2, value(type=$file)
     parameter p3, value(type=$file)
     parameter p4, value(type=$file)
     parameter p5, value(type=$file)
     parameter p6, value(type=$file)
     parameter p7, value(type=$file)
     parameter p8, value(type=$file)
qualifier q1, placement=local
qualifier q2, value(type=a_and_b, list, required), placement=local
define type a_and_b
     keyword a, value(type=$number, required)
     keyword b, value(type=$number, required)
$ type fun.pas
[inherit('sys$library:pascal$cli_routines')]
program fun(input,output);

type
    pstr = varying [255] of char;

procedure check(pn : pstr);

var
    fnm, a, b : pstr;

begin
    if odd(cli$present(pn)) then begin
       cli$get_value(pn, fnm.body, fnm.length);
       write(pn, '=', fnm);
       if odd(cli$present('Q1')) then begin
          write(' Q1=present')
       end else begin
          write(' Q1=notpresent')
       end;
       if odd(cli$present('Q2')) then begin
          cli$get_value('Q2.A', a.body, a.length);
          write(' A=', a);
          cli$get_value('Q2.B', b.body, b.length);
          write(' B=', b);
       end;
       writeln;
    end;
end;

begin
    check('P1');
    check('P2');
    check('P3');
    check('P4');
    check('P5');
    check('P6');
    check('P7');
    check('P8');
end.
$ pas fun
$ lin fun
$ set comm fun
$ fun x.dat /q2=(a:1,b:2) y.dat /q1 /q2=(a:3,b:4) z.dat /q2=(a:5,b:6)
P1=x.dat Q1=notpresent A=1 B=2
P2=y.dat Q1=present A=3 B=4
P3=z.dat Q1=notpresent A=5 B=6

Arne