Linux Certif

Toute la documentation sur la certification Linux LPI

fork

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fork - »Ò¥×¥í¥»¥¹¤òÀ¸À®¤¹¤ë

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#include <sys/types.h>
#include <unistd.h>

pid_t fork(void);

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»Ò¥×¥í¥»¥¹¤Ï¿Æ¥×¥í¥»¥¹¤«¤é¥»¥Þ¥Õ¥©Ä´À° (semop(2)) ¤ò°ú¤­·Ñ¤¬¤Ê¤¤¡£

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»Ò¥×¥í¥»¥¹¤Ï¿Æ¥×¥í¥»¥¹¤«¤é¥ì¥³¡¼¥É¥í¥Ã¥¯ (fcntl(2)) ¤ò°ú¤­·Ñ¤¬¤Ê¤¤¡£

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»Ò¥×¥í¥»¥¹¤Ï¿Æ¥×¥í¥»¥¹¤«¤é¥¿¥¤¥Þ¡¼ (setitimer(2) alarm(3), timer_create(3)) ¤ò°ú¤­·Ñ¤¬¤Ê¤¤¡£

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»Ò¥×¥í¥»¥¹¤Ï¿Æ¥×¥í¥»¥¹¤«¤é¼ç¤À¤Ã¤¿ÈóƱ´ü I/O Áàºî (aio_read(3), aio_write(3)) ¤ò°ú¤­·Ñ¤¬¤Ê¤¤¡£

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»Ò¥×¥í¥»¥¹¤Ï¿Æ¥×¥í¥»¥¹¤«¤é¥Ç¥£¥ì¥¯¥È¥êÊѹ¹ÄÌÃÎ (dnotify) (fcntl(2) ¤Ë¤ª¤±¤ë F_NOTIFY ¤ÎÀâÌÀ¤ò»²¾È) ¤ò°ú¤­·Ñ¤¬¤Ê¤¤¡£

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prctl(2) ¤Î PR_SET_PDEATHSIG ¤ÎÀßÄ꤬¥ê¥»¥Ã¥È¤µ¤ì¡¢»Ò¥×¥í¥»¥¹¤Ï¿Æ¥×¥í¥»¥¹¤¬½ªÎ»¤·¤¿¤È¤­¤Ë ¥·¥°¥Ê¥ë¤ò¼õ¿®¤·¤Ê¤¤¡£

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madvise(2) ¤Î MADV_DONTFORK ¥Õ¥é¥°¤Ç¥Þ¡¼¥¯¤µ¤ì¤¿¥á¥â¥ê¥Þ¥Ã¥Ô¥ó¥°¤Ï¡¢ fork(2) ¤Ë¤è¤Ã¤Æ°ú¤­·Ñ¤¬¤ì¤Ê¤¤¡£

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»Ò¥×¥í¥»¥¹¤Î½ªÎ»¥·¥°¥Ê¥ë¤Ï¾ï¤Ë SIGCHLD ¤Ç¤¢¤ë (clone(2) ¤ò»²¾È)¡£

¤µ¤é¤Ë°Ê²¼¤ÎÅÀ¤Ë¤Ä¤¤¤ÆÃí°Õ¤¹¤ë¤³¤È:

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EAGAIN

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EAGAIN

¸Æ¤Ó½Ð¤·¸µ¤Î RLIMIT_NPROC »ñ¸»¤ÎÀ©¸Â (resource limit) ¤Ë㤷¤¿¤¿¤á¤Ë¡¢¿·¤·¤¤¥×¥í¥»¥¹¤òÀ¸À®¤Ç¤­¤Ê¤«¤Ã¤¿¡£ ¤³¤ÎÀ©¸Â¤òĶ¤¨¤ë¤Ë¤Ï¡¢¥×¥í¥»¥¹¤Ï CAP_SYS_ADMIN ¤Þ¤¿¤Ï CAP_SYS_RESOURCE ¥±¡¼¥Ñ¥Ó¥ê¥Æ¥£ (capability) ¤ò»ý¤¿¤Ê¤¯¤Æ¤Ï¤Ê¤é¤Ê¤¤¡£

ENOMEM

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½àµò

SVr4, 4.3BSD, POSIX.1-2001.

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Linux ¤Ç¤Ï¡¢ fork() ¤ò ½ñ¤­¹þ¤ß»þ¥³¥Ô¡¼ (copy-on-write)¡¦¥Ú¡¼¥¸¤òÍѤ¤¤Æ¼ÂÁõ¤·¤Æ¤¤¤ë¡£ ¤·¤¿¤¬¤Ã¤Æ¡¢fork ¤ò¹Ô¤¦¤³¤È¤ÎÍ£°ì¤Î¥Ç¥á¥ê¥Ã¥È¤Ï¡¢ ¿Æ¥×¥í¥»¥¹¤Î¥Ú¡¼¥¸¡¦¥Æ¡¼¥Ö¥ë¤òÊ£À½¤È »Ò¥×¥í¥»¥¹¼«¿È¤Î¥¿¥¹¥¯¹½Â¤¤ÎºîÀ®¤Î¤¿¤á¤Î»þ´Ö¤È¥á¥â¥ê¤¬É¬Íפʤ³¤È¤Ç¤¢¤ë¡£

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pipe(2) ¤ª¤è¤Ó wait(2) ¤ò»²¾È¡£

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clone(2), execve(2), setrlimit(2), unshare(2), vfork(2), wait(2), capabilities(7)