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

pid_t fork(void);

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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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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¤¤¡£

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¥á¥â¥ê¤¬Â­¤ê¤Ê¤¤¤¿¤á¤Ë¡¢ fork() ¤ÏɬÍפʥ«¡¼¥Í¥ë¹½Â¤ÂΤò³ä¤êÅö¤Æ¤ë¤³¤È¤¬¤Ç¤­¤Ê¤«¤Ã¤¿¡£

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SVr4, 4.3BSD, POSIX.1-2001.

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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)