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📁 一份很好的linux入门资料
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<HTML><HEAD>  <TITLE>BBS水木清华站∶精华区</TITLE></HEAD><BODY><CENTER><H1>BBS水木清华站∶精华区</H1></CENTER>发信人:&nbsp;holly&nbsp;(holly),&nbsp;信区:&nbsp;Linux&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<BR>标&nbsp;&nbsp;题:&nbsp;Re:&nbsp;在读Linux源代码遇到的问题&nbsp;<BR>发信站:&nbsp;BBS&nbsp;水木清华站&nbsp;(Tue&nbsp;Nov&nbsp;&nbsp;9&nbsp;11:23:16&nbsp;1999)&nbsp;<BR>&nbsp;<BR>【&nbsp;在&nbsp;limbo&nbsp;(每日逢君不见君)&nbsp;的大作中提到:&nbsp;】&nbsp;<BR>&nbsp;<BR>faint,&nbsp;回这篇文章中间华东南地区网的路由断了&nbsp;3&nbsp;次,&nbsp;<BR>于是我就写了三次...&nbsp;<BR>&nbsp;<BR>∶<I>&nbsp;现在读include\asm-i386\bitops.h的一段代码时，几如读天书，这段代码如下：&nbsp;</I><BR>∶<I>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;extern&nbsp;__inline__&nbsp;void&nbsp;set_bit(int&nbsp;nr,&nbsp;volatile&nbsp;void&nbsp;*&nbsp;addr)&nbsp;</I><BR>∶<I>&nbsp;&nbsp;&nbsp;&nbsp;{&nbsp;</I><BR>∶<I>&nbsp;&nbsp;__asm__&nbsp;__volatile__(&nbsp;LOCK_PREFIX&nbsp;</I><BR>∶<I>&nbsp;&nbsp;&nbsp;&quot;btsl&nbsp;%1,%0&quot;&nbsp;</I><BR>∶<I>&nbsp;&nbsp;&nbsp;:&quot;=m&quot;&nbsp;(ADDR)&nbsp;</I><BR>∶<I>&nbsp;&nbsp;&nbsp;:&quot;ir&quot;&nbsp;(nr));&nbsp;</I><BR>∶<I>&nbsp;&nbsp;&nbsp;&nbsp;}&nbsp;</I><BR>∶<I>&nbsp;&nbsp;&nbsp;&nbsp;问题：&nbsp;</I><BR>∶<I>&nbsp;&nbsp;&nbsp;&nbsp;(1)&nbsp;__asm__&nbsp;是什么意思？&nbsp;难道和编译器有关？&nbsp;</I><BR>&nbsp;<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;inline&nbsp;assembler&nbsp;of&nbsp;gcc&nbsp;<BR>&nbsp;<BR>∶<I>&nbsp;&nbsp;&nbsp;&nbsp;(2)&nbsp;__volatile__&nbsp;是什么意思？&nbsp;</I><BR>&nbsp;<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;inhibit&nbsp;the&nbsp;optimization&nbsp;in&nbsp;these&nbsp;codes.&nbsp;Let&nbsp;the&nbsp;gcc&nbsp;create&nbsp;codes&nbsp;<BR>according&nbsp;to&nbsp;the&nbsp;assembler&nbsp;codes&nbsp;restrictly&nbsp;<BR>&nbsp;<BR>∶<I>&nbsp;&nbsp;&nbsp;&nbsp;(3)&nbsp;LOCK_PREFIX&nbsp;是什么意思？&nbsp;</I><BR>∶<I>&nbsp;&nbsp;&nbsp;&nbsp;(4)&nbsp;&quot;btsl&nbsp;%1,&nbsp;%0&quot;&nbsp;似乎是一个汇编指令，&nbsp;我可以查到这是什么指令吗？&nbsp;如何查？&nbsp;</I><BR>&nbsp;<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Look&nbsp;the&nbsp;Intel's&nbsp;i386&nbsp;instruction&nbsp;manual.&nbsp;NOTE&nbsp;gcc&nbsp;uses&nbsp;AT&amp;T&nbsp;format,&nbsp;<BR>not&nbsp;Intel&nbsp;format.&nbsp;<BR>&nbsp;<BR>∶<I>&nbsp;&nbsp;&nbsp;&nbsp;(5)&nbsp;:(ADDR)&nbsp;似乎是&nbsp;%1&nbsp;或&nbsp;%0所对应的值，是对应%1还是%0?&nbsp;&quot;=m&quot;似乎是参数？&nbsp;</I><BR>&nbsp;<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&quot;=m&quot;,&nbsp;output&nbsp;to&nbsp;memory&nbsp;directive,&nbsp;the&nbsp;mmeory&nbsp;address&nbsp;is&nbsp;ADDR&nbsp;<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ADDR&nbsp;-&gt;&nbsp;%0,&nbsp;nr&nbsp;-&gt;&nbsp;%1&nbsp;<BR>&nbsp;&nbsp;<BR>∶<I>&nbsp;&nbsp;&nbsp;&nbsp;(6)&nbsp;以上这些问题的解决我可以查什么资料呢？&nbsp;</I><BR>&nbsp;&nbsp;&nbsp;&nbsp;<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;info&nbsp;gcc&nbsp;<BR>&nbsp;<BR>&nbsp;<BR>--&nbsp;<BR>※&nbsp;来源:·BBS&nbsp;水木清华站&nbsp;bbs.net.tsinghua.edu.cn·[FROM:&nbsp;202.120.13.24]&nbsp;<BR><CENTER><H1>BBS水木清华站∶精华区</H1></CENTER></BODY></HTML>
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