Linux???????Linux????

????Linux?????
??????????????Linux?????????????????????????User Space?????????Kernel Space????

???????????а?????C?????????ó??????Щ???????л???????shell?????shell??????Linux????в?????????????
????????????????????????????????????????y???
???????κ??????????????У?????????????????????
?????????????????????linux???????÷??????linux??????÷??????????????????????????????????????????????????????????Ч???
?????????????????????????????????CPU?????????????????????
??????ARM?????ARM?????7????????????????CPU??????е???????????????????? (1)????? usr (2)???? sys(3)?????? svc(4)?????ж? fiq(5)???ж? irq(6)?????????? abt(7)δ???????????????κ?????????????????????????ü???????????????????????е????????????????????????????????μ????“?????????”????????????????????“?????????”???????????鼮??
??????X86?????X86?????4??????????????Ring0—Ring3 ;Ring0?????????????????????IO?豸??Ring3???к???????
??????????????Android??????????????“??????”??Android???е?APK??ó?????????Java????????????У???ó???????????
???????????????????????????е?????????????????????“??????”??“????ж?”?????????????????????
????Linux????
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????????????????Linux???????

????SCI??System Call Interface??????????????????????????????????????????????Linux????????Linux????????????????κ???????????????????????????????????????Linux?У???????????????????????????????????????????????
????PM??Procees Management?????????????????崴???????????fork??exec???????????kill??exit??????????????????????signal??????????????????????????????ι???CPU???????????Linux???????????д?????????????????????????????????Щ????????紴?????????????????
????MM??Memory Management???????????????????????????????????????????
????VFS??Virtual File Systems???????????????????????????????????????????????????????Linux??“??н????”????Щ????????VFS???????Linux?????????????????????????????????????????????????????????????????????????????

????Device Drivers?豸????????????????????????????Linux??????д???????????豸???????????????????????????豸??
????Linux??????????????豸?????豸??????豸???????豸??????????д?????????豸???????豸?????????????????????????豸??????豸?к??????????
????????Э?????Linux????????????????Э??????
????????Linux?????????????????linux???????Linux????
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