Re: Fun trick

On 1/8/2025 2:36 PM, Arne Vajhøj wrote:

On 1/8/2025 12:37 PM, John Reagan wrote:

On 1/7/2025 8:58 PM, Arne Vajhøj wrote:

During some troubleshooting over at VSI forum hb told me that
running a shareable image will execute LIB$INITIALIZE
functions.
>
That made me write this:

...

Pascal has an [INITIALIZE] attribute that you can put on the PROCEDURE CHECK and the compiler should do the contribution to the LIB$INITIALIZE PSECT.
>
And you should include LIB$INITIALIZE (the code module, not the data PSECT) from STARLET when linking.  The x86 linker will do that for you, but the Alpha and Itanium linkers do not.

 Zweite Sehr Verbesserte Ausgabe:
 $ type lib.pas
[inherit('sys$library:pascal$lib_routines', 'sys$library:starlet')]
module lib(input, output);
 [initialize]
procedure check;
 var
    imgnam : varying [1024] of char;
 begin
    lib$getjpi(item_code := jpi$_imagname, resultant_string := imgnam.body, resultant_length := imgnam.length);
    if index(imgnam, ']libshr.EXE') > 0 then begin
       writeln('This is a shareable image to link against not run');
       $exit(ss$_normal);
    end;
end;
 [global]
procedure say;
 begin
    writeln('Hi');
end;
 end.
$ type prg.pas
program prg(input,output);
 [external]
procedure say; external;
 begin
    say;
end.
$ pas lib
$ link/share=libshr lib + sys$library:starlet/lib/incl=lib$initialize + sys$input/opt
SYMBOL_VECTOR=(say=PROCEDURE)
$
$ define/nolog libshr sys$disk:[]libshr
$ pas prg
$ link prg + sys$input/opt
libshr/share
$
$ run prg
Hi
$ run libshr
This is a shareable image to link against not run
 Arne
 

And the compiler also supports the Extended Pascal TO BEGIN DO and TO END DO statements.  TO BEGIN DO is just the same as [INITIALIZE] but allows any statement.  TO END DO is an exit handler (registered with an initialization routine).