{var%20f='http://v.t.sina.com.cn/share/share.php?appkey=1515056452',u=z||d.location,p=['&url=',e(u),'&title=',e(t||d.title),'&source=',e(r),'&sourceUrl=',e(l),'&content=',c||'gb2312','&pic=',e(p||'')].join('');function%20a(){if(!window.open([f,p].join(''),'mb',['toolbar=0,status=0,resizable=1,width=440,height=430,left=',(s.width-440)/2,',top=',(s.height-430)/2].join('')))u.href=[f,p].join('');};if(/Firefox/.test(navigator.userAgent))setTimeout(a,0);else%20a();})(screen,document,encodeURIComponent,'','','https://www.manongdao.com/data/attach/logo/logo.png', '推荐 姐就是有狂的资本 的问题《How to handle unknown dependencies in Makefile tha》','https://www.manongdao.com/q-1030411.html','页面编码gb2312|utf-8默认gb2312'));){kind=link}
Let's say my Makefile is building a website. I write a index.html containing assets, like this:
<html>
<body><img src="asset/foo.img"/></body>
</html>
Now I want to write a rule to create a ZIP archive that contains the HTML as well as its assets.
I write a script to parse out the src= attributes, but what do I do with it?
If I put that in a recipe, but at that point the Makefile rules can't be changed.
If I put it in a $(shell ...) command, then it will have to run every time the Makefile is parsed, even if the user is doing a clean or something.
What is the proper way to handle such a scenario?
Actually I think I just figured it out myself. The solution is a sub-call to
$(MAKE)—in fact, its primary difference compared toincludeseems to be the fact that it occurs at recipe execution time rather than at parse time.Something like this, maybe:
I seem to miss your problem. Isn't it that a dependency tree of your situation looks like this:
where "1" is the rule which scans
my_page.htmlfor all assets and writes them back todepend.dep(or the makefile itself, that doesn't change the solution) and "2" is updating the zip file with changed member files? As make is trying to re-makedepend.dep(ormakefileitself) prior to any other rule, you always have an up-to-date dependency list when starting a make-run which will do exactly as you command: add/update members toarchive.zipif they are newer. I say it again: re-parsingmy_page.htmlif it has changed relative to the dependencies is step zero in a make-run, if there exists a dependency towards a file which isincluded ormakefileitself.