Re: Fun trick

On 1/13/2025 5:55 PM, Arne Vajhøj wrote:

On 1/13/2025 5:18 PM, Lawrence D'Oliveiro wrote:

On Mon, 13 Jan 2025 13:45:50 -0500, Arne Vajhøj wrote:

There are probably a lot of shareable images written in C out there
where the developer has no idea that they are runnable or what code will
run.

>
If it has no main(), then nothing will run.

 That is what the developer thinks.
 But it is not so.
 $ type lawrence.c
#include <stdio.h>
 int foobar()
{
     printf("Hi Lawrence\n");
     return 1;
}
$ cc lawrence
$ link/share  lawrence
$ run lawrence
Hi Lawrence
 No main() and it runs anyway.
 Arne
 

COBOL paragraphs behave like C.  First routine/PARAGRAPH gets a WEAK transfer address.  Linker finds the first one.  Shuffle modules around and you'll get different transfer addresses.  Pascal just creates a STRONG transfer address for a PROGRAM statement.