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From: dave@cs.arizona.edu (Dave P. Schaumann)
Newsgroups: comp.sys.amiga.programmer
Subject: Re: How are some programs SO DAMN SMALL!
Summary: It's the link files
Message-ID: <702@caslon.cs.arizona.edu>
Date: 21 Jan 91 00:04:08 GMT
References: <1991Jan20.210328.18087@hoss.unl.edu>
Organization: U of Arizona CS Dept, Tucson
Lines: 44

In article <1991Jan20.210328.18087@hoss.unl.edu> 231b3678@fergvax.unl.edu (CS 231 section 2) writes:
>I was looking through some programs that were written in C, and I noticed that
>a few were really SMALL!  Like only 2k for a full-blown clock.  How does the
>program get so small!  It seems that if I compile a program like
> 
>#include <stdio.h>
>main(){printf("hey man!\n");}

The reason even a minimal C program, ie "main(){}" compiles to ~4K is that it
you have to link it to the run-time library.  This has code for stuff like
parsing the command line, and setting up stdin/stdout.  If you had something
like "main(){real x; x = 0.0;}", it would be even larger, because now you
would be bringing in all the f.p. routines as well.

>the result is 4424 bytes, OPTIMIZED and all.  How can a HUGE clock compile
>smaller then a printf statement.
> 
>[...]
> 
>Can 'C' code get small?  I have a LIST program in the works.  It's 14000
>bytes compared to c:list's 2500.  Assembly must be the only decent way to
>go.

As you guessed, if you want *really* small code, you have to use assembler.
Then you only have the code you need to run your program, and no extra hidden
stuff.

As an aside, I would like to point out that unless you're writing something
that is extremely time critical, or *every* *byte* *counts*, writing a whole
program in assembly is probably overkill.  Masochists & obsessives are, of
course, exempt.

Real time simulations are a good example if the former, and utilities that
are permenantly resident (like a system clock) or used frequently are good
examples of the latter.

>     "These are not ASUN's, DN's, or                        Phil Dietz 
>      the Regent's opinions.  Therefore       231b3678@fergvax.unl.edu       
>      they aren't full of 'filler.'"                 Univ. of Nebraska

Python disclaimer: "It was one of Wilde's!"

Dave Schaumann		|  And then -- what then?  Then, future...
dave@cs.arizona.edu	|  		-Weather Report