Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!uflorida!ukma!xanth!mcnc!rti!sas!toebes
From: toebes@sas.UUCP (John Toebes)
Newsgroups: comp.sys.amiga
Subject: Re: Linking without startup code or libraries
Message-ID: <971@sas.UUCP>
Date: 16 Mar 89 18:40:25 GMT
References: <DEVEN.89Mar1183038@daniel.pawl.rpi.edu> <92203@sun.uucp> <DEVEN.89Mar3010734@daniel.pawl.rpi.edu> <92710@sun.uucp>
Reply-To: toebes@sas.UUCP (John Toebes)
Distribution: na
Organization: SAS Institute Inc, Cary NC
Lines: 48

In article <92710@sun.uucp> cmcmanis@sun.UUCP (Chuck McManis) writes:
>In article <92203@sun.uucp> I wrote:
>> Yes, with Lattice 5.0x it is possible to have nothing but 
>> blink myprog.o to myprog
>This is correct.
>> Essentially, you will have to define your lib pointers internally and use
>> the prototypes for direct linkage to the libraries.
>
>Then in a followup article shadow@pawl.rpi.edu writes:
>> Can you give me a short simple example that will work for this?  Say,
>> the classic "Hello, world!" program?  I tried something like this:
>
>To which I reply "Certainly" and here it is :
>  ... example deleted ...
Actually this question has come up quite frequently and there turns out to
be an even smaller solution that is made possible with 5.0 that has the
additional advantage of being RESIDENTABLE!

#include <exec/types.h>
#include <proto/exec.h>
#include <proto/dos.h>
#include <strings.h>

#define MSG(f,s) Write(f,s,strlen(s))

void tinyhello()
{
struct DosLibrary *DOSBase;  /* NOTE it is a local variable */
if ((DOSBase = (struct DosLibrary *)OpenLibrary("dos.library",0)) != NULL)
   {
   MSG(Output(), "Hello World\n");
   CloseLibrary((struct Library *)DOSBase);
   }
}

Compile this with
  LC -cs -v tinyhello
  blink tinyhello.o

Note that if you use the -cs option, the strings will be put into the code
section automatically.  Since the library base for the call is a local 
variable (a trick added under 5.0) and the strings are accessed pc-relative,
there is no need to have A4 set up.  This trick is used in POPCLI 4 and
also in the Avail program on the Lattice diskettes.  Enjoy.

>--Chuck McManis
>uucp: {anywhere}!sun!cmcmanis   BIX: cmcmanis  ARPAnet: cmcmanis@sun.com
>These opinions are my own and no one elses, but you knew that didn't you.