[e-mail]

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???????????
????? 3???? ????
?8???9? ??????

• ????????? ?
• yaoki_at_sic.shibaura-it.ac.jp
• sasano_at_sic.shibaura-it.ac.jp

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???web page?
???web page http//www.sic.shibaura-it.ac.jp/
sasano/lecture/lecture.html
??????? sasano_at_sic.shibaura-it.ac.jp
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???????

• ????,????,????(????????)???????????????????
• ????????????(??????????)
• ???????????????????????????????
• ?30??????

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(No Transcript)
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???????
????????????? Ctrl_C ?? Ctrl_Z ???? fg
?? ?????????? ???ps ef??????????????????????
kill -STOP ?????? kill -CONT ?????? kill INT
?????? ????
int main () int i0 for (1i)
sleep (1) printf ("hello d\n",i)
return (0)
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?????????????signal()???????
?????????????
???????????????????????????
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Signal??????????1

• Ctrl-C????????????????
• 2????????????

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include ltsignal.hgt / signal???
SIGINT, SIG_DFL??????
/ include ltstdio.hgt / printf???
/ include ltunistd.hgt / sleep??? / void f
(int sig) printf("I got signal d\n",
sig) signal(SIGINT, SIG_DFL) int
main() signal(SIGINT, f) while(1)
printf("Hello World!\n")
sleep(1)
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Signal??????????2

• ?????????????????????????,15?????????????
• ??????setsigint.c

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??????????3

• ???parent.c
• ???????????????wait()??????????????????,??????????
  
• ??
• ????????????,??????????????????????,wait()????????
  ????, SIGCHLD???
• ???????????????!

?????? parent_sig.c
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???????
???parent_sig.c????????3??? ?????execl??????childA
, childB, childC???????execl????????? ????????????
??????????????(execl???????????? ?????????????????
??????????????????????????????????????????????????
)
fork????????3?????????????? ???????(main?????????
?????)?????????
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??????????
signal???????????????????????????SIGKILL(9)?SIGSTO
P(19)????????????????
SIGKILL --- ??????? SIGSTOP --- ?????????
??????(root)??????????????????????????????????????
???
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????????????
??????? ??????????(?????????????????? UNIX?OS?????
????)??????????? ????????????? ???(???????????)???
????? ?????????????????????? ????????????????????
????? 1???????????????????????? ??????(SIGKILL????
?)???????????
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?????????????
????(??????????) CPU???????????
??????(CPU???????) --- CPU????????????????
???????? ??????(CPU?????) ??????
--- CPU????1??
??????????????? ??????????????????
???????????CPU??????????? ??????????????(?????
)??? ????(??????????) ????????????????????????????
????(kill??????????????) (??) ????????(?????)?UNI
X??????????????(signal????????????)
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??????

• ???????????????
• ??????????????????
• ?)?????????????????????
• ????SIGALRM
• ???????alarm(), pause() ???

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alarm()?pause()
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??????(alarm) ?1

• setalarm.c
• ??????????????
• alarm()???,???????
• ????(??????sec)
• ./setalarm 10

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????????????
kill ????????????
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????????????
kill ???????????
kill??????????????????ID? ??????????ID????????????
? ??????????????ID???????????? ????????? ????ID
1?(init????)????????????????? (init???????????????
????????? ??????????????????????)
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??? 2

• sendsigint.c (???progexef.c???)
• ????????????????
• ???????????????,???????????
• ????
• ./sendsigint setsigint

?????
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????1
?????????Ctrl-C?3???????????????????
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????2
Ctrl-C???????????????? ??????????? (???????sleep?
???????????????Global???Ctrl-C?????????????)
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????3
???????????????(??????ID?)????????????????????????
? kill(pid, 0)????? pid?1??32767????????
(??) ??????ID????????????????????? kill(pid,
0)?????????(????0???)?pid???? ???ID?????ID????