Message-Id: <m0yDU2P-000S3BC@inti.gov.ar>
Comments: Authenticated sender is <salvador AT natacha DOT inti DOT gov DOT ar>
From: "Salvador Eduardo Tropea (SET)" <salvador AT inti DOT gov DOT ar>
Organization: INTI
To: mheumann AT post DOT uni-bielefeld DOT de (Manni Heumann), djgpp AT delorie DOT com
Date: Fri, 13 Mar 1998 16:00:04 +0000
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Subject: Re: The miracle of MAKE
In-reply-to: <EprLsF.DyI@hermes.hrz.uni-bielefeld.de>
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mheumann AT post DOT uni-bielefeld DOT de (Manni Heumann) wrote:

> I know, I am courios, but: How the hell does make know when to rebuild a file 
> an when it is up to date?
> It must have some kind of database somewhere and I really would like to know 
> where!

No magic, no database (at least in no in normal cases):
Make uses the time stamp of the files, you define the dependencies in the 
makefile and make just takes a look to the files to see if some action is 
needed. If you modify one of your source files the time stamp is updated and 
hence it indacates a newer value than your .o file then make compiles the .c 
file into a .o file, but now the .o file have a newer date (newer than the exe) 
and hence make creates the .exe.

SET
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