Linux Certif

Toute la documentation sur la certification Linux LPI

openat

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#define _ATFILE_SOURCE

#include <fcntl.h>



int openat(int dirfd, const char *pathname, int flags);

int openat(int dirfd, const char *pathname, int flags, mode_t mode);

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pathname ¤Ç»ØÄꤵ¤ì¤ë¥Ñ¥¹Ì¾¤¬ÁêÂХѥ¹¤Ç¤¢¤ë¾ì¹ç¡¢ ¥Õ¥¡¥¤¥ë¥Ç¥£¥¹¥¯¥ê¥×¥¿ dirfd ¤Ç»²¾È¤µ¤ì¤ë¥Ç¥£¥ì¥¯¥È¥ê¤«¤é¤ÎÁêÂХѥ¹Ì¾¤È¤·¤Æ²ò¼á¤µ¤ì¤ë (open(2) ¤Ç¤Ï¡¢ÁêÂХѥ¹¤Ï¸Æ¤Ó½Ð¤·¸µ¥×¥í¥»¥¹¤Î¥«¥ì¥ó¥È¥ï¡¼¥­¥ó¥°¥Ç¥£¥ì¥¯¥È¥ê¤«¤é¤Î ÁêÂХѥ¹¤È¤Ê¤ë)¡£

pathname ¤¬ÁêÂХѥ¹¤Ç¤¢¤ê¡¢¤«¤Ä dirfd ¤¬ÆÃÊ̤ÊÃÍ AT_FDCWD ¤Ç¤¢¤ë¾ì¹ç¡¢ pathname ¤Ï (open(2) ¤ÈƱ¤¸¤è¤¦¤Ë) ¸Æ¤Ó½Ð¤·¸µ¥×¥í¥»¥¹¤Î ¥«¥ì¥ó¥È¥ï¡¼¥­¥ó¥°¥Ç¥£¥ì¥¯¥È¥ê¤«¤é¤ÎÁêÂХѥ¹Ì¾¤È¤·¤Æ²ò¼á¤µ¤ì¤ë¡£

pathname ¤¬ÀäÂХѥ¹¤Ç¤¢¤ë¾ì¹ç¡¢ dirfd ¤Ï̵»ë¤µ¤ì¤ë¡£

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dirfd ¤¬Í­¸ú¤Ê¥Õ¥¡¥¤¥ë¥Ç¥£¥¹¥¯¥ê¥×¥¿¤Ç¤Ê¤¤¡£

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2 ¤ÄÌܤÎÍýͳ¤Ï¡¢ ¥¢¥×¥ê¥±¡¼¥·¥ç¥ó¤Ë¤è¤Ã¤Æ´ÉÍý¤µ¤ì¤ë¥Õ¥¡¥¤¥ë¥Ç¥£¥¹¥¯¥ê¥×¥¿ (·²) ¤ò»È¤¦¤³¤È¤Ç¡¢ openat() ¤¬¥¹¥ì¥Ã¥ÉËè¤Î¤¤¤ï¤æ¤ë¡Ö¥«¥ì¥ó¥È¥ï¡¼¥­¥ó¥°¥Ç¥£¥ì¥¯¥È¥ê¡×¤ò¼ÂÁõ¤Ç¤­¤ë¤¿¤á¤Ç¤¢¤ë¡£ (¤³¤Îµ¡Ç½¤Ï /proc/self/fd/dirfd ¤ò»È¤Ã¤¿Î¢µ»¤Ç¤â¼Â¸½¤Ç¤­¤ë¤¬¡¢¤¢¤Þ¤ê¸úΨŪ¤Ç¤Ï¤Ê¤¤)¡£

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faccessat(2), fchmodat(2), fchownat(2), fstatat(2), futimesat(2), linkat(2), mkdirat(2), mknodat(2), open(2), readlinkat(2), renameat(2), symlinkat(2), unlinkat(2), mkfifoat(3), path_resolution(7)