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wait, waitpid, wait4, wait3 — ?ץ??????ν?λ?Ե?

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Standard C Library (libc, -lc)

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<sys/types.h> <sys/wait.h> pid_t wait(int *status) <sys/time.h> <sys/resource.h> pid_t waitpid(pid_t wpid, int *status, int options) pid_t wait3(int *status, int options, struct rusage *rusage) pid_t wait4(pid_t wpid, int *status, int options, struct rusage *rusage)

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wait() ?ؿ??ϡ???λ?????ҥץ??????? status ???󤬻??ѤǤ????褦?ˤʤ??ޤǡ??ޤ??ϥ????ʥ????????????ޤǡ? ?ƤӽФ??ץ??????μ¹Ԥ????ߤ??ޤ??? wait() ?ƤӽФ????????????ȡ? status ?ΰ??ˤϲ????????Τ褦?˽?λ?????ץ??????ν?λ???????????ޤ???

wait4() ?????ƥॳ?????ϡ??????λҥץ????????Ԥ?ɬ?פ????ꡢ?ҥץ??????????Ѥ??? ?꥽???????????פ??뤤?ϥ??ץ???????ɬ?פȤ????ץ????????Τ????ˡ? ????????Ū?ʥ??󥿥ե????????󶡤??ޤ??? ????¾???Ե??ؿ??ϡ? wait4() ?????Ѥ??Ƽ????????Ƥ??ޤ???

wpid ???????ԤĤ٤??ҥץ??????ν????????ꤷ?ޤ??? wpid ?? -1 ?Ǥ??????硢???θƤӽФ??Ϥ??٤Ƥλҥץ????????Ԥ??ޤ??? wpid ?? 0 ?Ǥ??????硢???θƤӽФ??ϡ??ƤӽФ?¦?Υץ????????롼?פ? ???٤Ƥλҥץ????????Ԥ??ޤ??? wpid ?? 0 ?????礭?????硢???θƤӽФ??ϥץ????? ID ?? wpid ?Ǥ????ץ????????Ԥ??ޤ??? wpid ?? -1 ???꾮???????硢?ƤӽФ??ϡ??ץ????????롼?? ID ?? wpid ???????ͤ????????ץ????????Ԥ??ޤ???

status ?????ϡ??ʲ??Τ褦???????????Ƥ??ޤ??? options ?????ˤϡ??ʲ???Ǥ?դΥ??ץ??????Υӥå??????¤??????ޤ??? WCONTINUED ???ץ??????ϡ????????ȥץ??????λҥץ??????ǡ????????????????߾??֤??? SIGCONT ?????ʥ??????????ä??????????ץ??????Υ??ơ??????? ???𤹤??٤??Ǥ??뤳?Ȥ򼨤??ޤ??? WNOHANG ???ץ??????ϡ????ơ??????????𤹤??ץ????????ʤ??????˸ƤӽФ??? ?֥??å????ʤ????Ȥ򼨤??????˻??Ѥ??ޤ??? WUNTRACED ???ץ??????????ꤹ???ȡ? SIGTTIN, SIGTTOU, SIGTSTP, SIGSTOP ?????ʥ??Τ????????ߤ??????????ȥץ??????λҤˤ⡢ ???Υ??ơ??????????𤵤??ޤ???

rusage ?? 0 ?ʳ??Ǥ????????ϡ???λ?????ץ??????? ???Τ??٤ƤλҤ????Ѥ????꥽?????Υ??ޥ꤬?֤????ޤ? (???ߤΤȤ????????ξ????????ߤ????ץ??????ˤĤ??Ƥϻ??ѤǤ??ޤ???)??

WNOHANG ???ץ????󤬻??ꤵ?졢???ơ??????????𤹤??ץ????????ʤ????硢 wait4() ?ϥץ????? ID 0 ???ᤷ?ޤ???

waitpid() ?ؿ??ϡ? rusage ???ͤ? 0 ?ˤ??? wait4() ??Ʊ???Ǥ??? ?Ť? wait3() ?ƤӽФ??ϡ? wpid ???ͤ? -1 ?ˤ??? wait4() ??Ʊ???Ǥ???

?ʲ??Υޥ????ϡ??ץ??????ν?λ?λ??????Τ??Τ˻??ѤǤ??ޤ??? ?ǽ??? 3 ?ĤΥޥ????ϡ?0 ?ʳ? (??) ???ͤ?ɾ?????ޤ?:

WIFCONTINUED(status)

?ץ?????????λ???Ƥ??餺?????????????????߾??֤Τ????????????????? ???Ȥʤ??ޤ??? ???Υޥ????? wait ?ƤӽФ??? WCONTINUED ???ץ????󤬻??ꤵ?줿?????Τ߿??Ȥʤ??ޤ???

WIFEXITED(status)

_exit(2) ?? exit(3) ???ƤӽФ????ץ????????????˽?λ?????????˿??Ȥʤ??ޤ???

WIFSIGNALED(status)

?????ʥ????????????????˥ץ?????????λ?????????˿??Ȥʤ??ޤ???

WIFSTOPPED(status)

?ץ?????????λ???Ƥ??ʤ????????ߤ??Ƥ??ƺƳ??Ǥ????????˿??Ȥʤ??ޤ??? ???Υޥ????? wait ?ƤӽФ??? WUNTRACED ???ץ??????????ꤹ?뤫???ҥץ????????ȥ졼???????Ƥ??? (ptrace(2) ?򻲾?) ?????Τߤ˿??Ȥʤ??ޤ???

?嵭?ޥ??????ͤ˽??äơ??ʲ??Υޥ????ϡ? ?ҥץ??????λĤ??Υ??ơ??????????????????ޤ?:

WEXITSTATUS(status)

WIFEXITED(status) ?????Ǥ????????ˡ??Ҥ? _exit(2) ?? exit(3) ???Ϥ????????β??? 8 ?ӥåȤ?ɾ?????ޤ???

WTERMSIG(status)

WIFSIGNALED(status) ?????Ǥ????????ˡ??ץ??????ν?λ?θ????Ȥʤä??????ʥ????ֹ???ɾ?????ޤ???

WCOREDUMP(status)

WIFSIGNALED(status) ?????Ǥ????????ˡ??ץ?????????λ???????ǡ??????ʥ????????????Ȥ??? ?ץ??????Υ??᡼?????ޤॳ???ե????뤬???????줿?????˿??Ȥʤ??ޤ???

WSTOPSIG(status)

WIFSTOPPED(status) ?????Ǥ????????ˡ??ץ??????????ߤθ????Ȥʤä??????ʥ????ֹ???ɾ?????ޤ???

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??λ?????ʥ??Υꥹ?ȤˤĤ??Ƥϡ? sigaction(2) ?򻲾Ȥ??Ƥ????????? ???ơ??????? 0 ?Ǥ????Ȥ??????Ȥϡ??????˽?λ?????Ȥ??????ȤǤ???

???٤Ƥλҥץ??????ν?λ???Ԥ????˿ƥץ?????????λ?????ȡ? ?Ĥ??λҥץ??????ˤϿƥץ????? ID ?? 1 (init ?Υץ????? ID) ?? ???????Ƥ????ޤ???

Ǥ?դ? wait() ?ƤӽФ?????α?ˤʤäƤ????֤˥????ʥ????????????ȡ? ?????ʥ??????롼?????????ä??Ȥ??ˡ? ?ƤӽФ??ϳ??????ޤ??뤫?Ƴ??????ޤ??? ?????ϥ????ʥ??˱ƶ????륪?ץ??????˰?¸???ޤ??? intro(2) ?????ƥॳ?????κƳ? (System call restart) ?ι??ܤ򻲾Ȥ??Ƥ?????????

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?ҥץ??????????ߤ???????λ?????????? wait() ?????ä??????ϡ??ҤΥץ????? ID ???ƤӽФ?¦?ץ????????ᤵ???ޤ??? ????¾?ξ????? -1 ???ᤵ?졢 errno ?????顼?򼨤??褦?????ꤵ???ޤ???

?ҥץ??????????ߤ???????λ?????????? wait4(), wait3(), waitpid() ?????ä??????ϡ??ҤΥץ????? ID ???ƤӽФ?¦?ץ????????ᤵ???ޤ??? ?ޤ? wait ?????Ƥ??ʤ??ҥץ???????¸?ߤ??ʤ??????ϡ?-1 ???ᤵ???? errno ?? ECHILD ?????ꤵ???ޤ??? WNOHANG ?????ꤵ?졢???ߤ????Ҥޤ??Ͻ?λ?????Ҥ??ʤ??????? 0 ???ᤵ???ޤ??? ???顼?????Ф????뤫???????????ʥ??ˤ??ꤳ?θƤӽФ????۾ｪλ?????????ϡ? -1 ???ᤵ?졢 errno ?????顼?򼨤??褦?????ꤵ???ޤ???

???顼

wait() ?ؿ??ϰʲ??ξ????˥??顼?Ȥʤꡢ?????????????ޤ?:

[ECHILD]

?ƤӽФ?¦?ץ??????ϡ?wait ?????Ƥ??ʤ??ҥץ????????????ޤ?????

[ECHILD]

?????ʥ? SIGCHLD ??̵?뤹?뤳?ȡ??ޤ??Ϥ??Υ????ʥ??? SA_NOCLDWAIT ?ե饰?????ꤹ?뤳?Ȥˤ??ꡢ?ƤӽФ?¦?Υץ??????ϴ??˥????ƥ??? ???Τ褦???????ͤ??Ѵ??????褦???׵ᤷ?Ƥ????Τǡ? ??λ???줿?ҥץ????????????????ͤ?̵?????Ȥ???ǽ?Ǥ???

[EFAULT]

status ?????? rusage ????????ˡ?ʥ??ɥ쥹???ؤ??Ƥ??ޤ??? (?ҥץ??????ν?λ???ˤϸ??Ф????ʤ????Ȥ??????ޤ???)

[EINTR]

?ƤӽФ????????????ʥ??ˤ??äƳ??????ޤ줿?????????ʥ??? SA_RESTART ?ե饰?????ꤵ???Ƥ??ޤ?????

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wait() ?ؿ??? waitpid() ?ؿ??? POSIX ?ˤ??ä??????????Ƥ??ޤ??? wait4() ?? wait3() ?? POSIX ?λ??ͤǤϤ????ޤ????? WCOREDUMP() ?ޥ???????????α???? wait() ?ƤӽФ????Ƴ????뵡ǽ?? POSIX ???󥿥ե??????γ?ĥ??ǽ?Ǥ???

??Ϣ????

_exit(2), ptrace(2), sigaction(2), exit(3)

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wait() ?ؿ??ϡ? Version 6 AT&T UNIX ???о줷?ޤ?????