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使用setjump loopjump在線程中跳轉(zhuǎn)的問(wèn)題跪求！

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qq_笑_17 2019-07-26 23:32:39

使用setjumploopjump在線程中跳轉(zhuǎn)的問(wèn)題使用setjump到另一個(gè)線程中跳轉(zhuǎn),跳轉(zhuǎn)成功了,后面的代碼不執(zhí)行了#define_CRT_SECURE_NO_WARNINGS#include#include#include#include#include#include#includejmp_bufbuf;void*print_a(void*);void*print_b(void*);//線程A方法void*print_a(void*a){for(inti=0;i

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江戶(hù)川亂折騰

TA貢獻(xiàn)1851條經(jīng)驗(yàn) 獲得超5個(gè)贊

講真，我沒(méi)想到還能這么用....setjmp/longjmpisimplementedbysavingtheregister(includingstackandcodepointeretc)whenfirstpassed,andrestoringthemjumping.當(dāng)線程b通過(guò)longjmp跳到print_a時(shí)，它的棧幀和線程a的棧幀所在的內(nèi)存就是一個(gè)地方了(原來(lái)?xiàng)５膬?nèi)存沒(méi)人管)。當(dāng)線程a退出時(shí)，自然要彈出所有棧幀，那么線程b之后對(duì)棧訪問(wèn)就是對(duì)非法內(nèi)存的訪問(wèn)了。就像你把雙胞胎中的弟弟的頭嫁接到哥哥身上，哥哥變成了連體嬰兒，哥哥掛掉之后，弟弟也活不成了，反之也是

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子衿沉夜

TA貢獻(xiàn)1828條經(jīng)驗(yàn) 獲得超3個(gè)贊

longjmp不能跨線程。C117.13.2.1/2:Thelongjmpfunctionrestorestheenvironmentsavedbythemostrecentinvocationofthesetjmpmacrointhesameinvocationoftheprogramwiththecorrespondingjmp_bufargument.Iftherehasbeennosuchinvocation,oriftheinvocationwasfromanotherthreadofexecution,orifthefunctioncontainingtheinvocationofthesetjmpmacrohasterminatedexecutionintheinterim,oriftheinvocationofthesetjmpmacrowaswithinthescopeofanidentifierwithvariablymodifiedtypeandexecutionhasleftthatscopeintheinterim,thebehaviorisundefined

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