Linux Certif

Toute la documentation sur la certification Linux LPI

getcontext

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getcontext, setcontext - ¥æ¡¼¥¶¥³¥ó¥Æ¥­¥¹¥È¤ò¼èÆÀ/ÀßÄꤹ¤ë

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#include <ucontext.h>

int getcontext(ucontext_t *ucp);
int setcontext(const ucontext_t *ucp);

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System V Ū¤Ê´Ä¶­¤Ç¤Ï¡¢ mcontext_t ¤ª¤è¤Ó ucontext_t ¤È¤¤¤¦ 2 ¤Ä¤Î·¿¤È¡¢ getcontext(), setcontext(), makecontext(3), swapcontext(3) ¤È¤¤¤¦ 4 ¤Ä¤Î´Ø¿ô¤¬ <ucontext.h> ¤ÇÄêµÁ¤µ¤ì¤Æ¤ª¤ê¡¢¤¢¤ë¥×¥í¥»¥¹ÆâÉô¤ÇÀ©¸æ²¼¤Ë¤¢¤ëÊ£¿ô¤Î¥¹¥ì¥Ã¥É´Ö¤Ç¡¢ ¥æ¡¼¥¶¥ì¥Ù¥ë¤Î¥³¥ó¥Æ¥­¥¹¥ÈÀÚÂؤ¨¤¬¤Ç¤­¤ë¤è¤¦¤Ë¤Ê¤Ã¤Æ¤¤¤ë¡£

mcontext_t ·¿¤Ï¥Þ¥·¥ó°Í¸¤Ç¡¢³°Éô¤«¤é¤Ï±£Ê䵤ì¤Æ¤¤¤ë¡£ ucontext_t ·¿¤Ï¹½Â¤ÂΤǡ¢¾¯¤Ê¤¯¤È¤â°Ê²¼¤Î 4 ¤Ä¤Î¥Õ¥£¡¼¥ë¥É¤ò»ý¤Ä¡£

typedef struct ucontext {

    struct ucontext *uc_link;

    sigset_t         uc_sigmask;

    stack_t          uc_stack;

    mcontext_t       uc_mcontext;

    ...

} ucontext_t;

sigset_t ¤È stack_t ¤Ï <signal.h> ¤ÇÄêµÁ¤µ¤ì¤Æ¤¤¤ë¡£ ¤³¤³¤Ç uc_link ¤Ï¡¢ ¸½ºß¤Î¥³¥ó¥Æ¥­¥¹¥È¤¬½ªÎ»¤·¤¿¤È¤­¡¢ ³¤¤¤ÆÀÚ¤êÂؤï¤ë¥³¥ó¥Æ¥­¥¹¥È¤Ø¤Î¥Ý¥¤¥ó¥¿¤Ç¤¢¤ë (¸½ºß¤Î¥³¥ó¥Æ¥­¥¹¥È¤¬ makecontext(3) ¤ÇÀ¸À®¤µ¤ì¤¿¤â¤Î¤Î¾ì¹ç)¡£ uc_sigmask ¤Ï¤³¤Î¥³¥ó¥Æ¥­¥¹¥È¤Ç¥Ö¥í¥Ã¥¯¤µ¤ì¤Æ¤¤¤ë ¥·¥°¥Ê¥ë·²¤Ç¤¢¤ë (sigprocmask(2) ¤ò¸«¤è)¡£ uc_stack ¤Ï¤³¤Î¥³¥ó¥Æ¥­¥¹¥È¤¬ÍѤ¤¤Æ¤¤¤ë¥¹¥¿¥Ã¥¯¤Ç¤¢¤ë (signalstack(2) ¤ò¸«¤è)¡£ uc_mcontext ¤ÏÊݸ¤µ¤ì¤Æ¤¤¤ë¥³¥ó¥Æ¥­¥¹¥È¤Î ¥Þ¥·¥óÆÃÍ­¤Îɽ¸½·Á¼°¤Ç¤¢¤ê¡¢ ¤³¤³¤Ë¤Ï¸Æ¤Ó½Ð¤·¤¿¥¹¥ì¥Ã¥É¤Î¥Þ¥·¥ó¥ì¥¸¥¹¥¿¤¬³ÊǼ¤µ¤ì¤ë¡£

getcontext() ´Ø¿ô¤Ï¡¢ ¥Ý¥¤¥ó¥¿ ucp ¤¬»Ø¤¹¹½Â¤ÂΤò¡¢ ¸½ºß¥¢¥¯¥Æ¥£¥Ö¤Ê¥³¥ó¥Æ¥­¥¹¥È¤Ë½é´ü²½¤¹¤ë¡£

setcontext() ´Ø¿ô¤Ï¡¢¥Ý¥¤¥ó¥¿ ucp ¤¬»Ø¤¹¥æ¡¼¥¶¥³¥ó¥Æ¥­¥¹¥È¤ò¥ê¥¹¥È¥¢¤¹¤ë¡£ ¸Æ¤Ó½Ð¤·¤ËÀ®¸ù¤¹¤ë¤ÈÊÖ¤é¤Ê¤¤¡£ ¤³¤Î¥³¥ó¥Æ¥­¥¹¥È¤Ï¡¢°ÊÁ°¤Ë getcontext() ¤Þ¤¿¤Ï makecontext(3) ¤ÇÆÀ¤é¤ì¤¿¤â¤Î¤«¡¢ ¤¢¤ë¤¤¤Ï¥·¥°¥Ê¥ë¤ÎÂè»°°ú¿ô¤È¤·¤ÆÍ¿¤¨¤é¤ì¤¿¤â¤Î¤Ë¤Ê¤ë¡£

¥³¥ó¥Æ¥­¥¹¥È¤¬ getcontext() ¤Î¸Æ¤Ó½Ð¤·¤Ë¤è¤Ã¤ÆÆÀ¤é¤ì¤Æ¤¤¤¿¤â¤Î¤Î¾ì¹ç¤Ï¡¢ ¥×¥í¥°¥é¥à¤Ï¤³¤Î¸Æ¤Ó½Ð¤·¤«¤éÊ֤ä¿Ä¾¸å¤«¤é¤Î¤è¤¦¤Ë¼Â¹Ô¤ò·Ñ³¤¹¤ë¡£

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SUSv2, POSIX.1-2001.

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sigaction(2), sigaltstack(2), sigprocmask(2), longjmp(3), makecontext(3), sigsetjmp(3)