Linux Certif

Toute la documentation sur la certification Linux LPI

sync_file_range

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sync_file_range - sync a file segment with disk

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#define _GNU_SOURCE

#include <fcntl.h>



int sync_file_range(int fd, off64_t offset, off64_t nbytes,

                    unsigned int flags);

ÀâÌÀ

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¥Ó¥Ã¥È¥Þ¥¹¥¯°ú¤­¿ô flags ¤Ë¤Ï°Ê²¼¤ÎÃͤò»ØÄꤹ¤ë¤³¤È¤¬¤Ç¤­¤ë:

SYNC_FILE_RANGE_WAIT_BEFORE

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SYNC_FILE_RANGE_WRITE

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SYNC_FILE_RANGE_WAIT_AFTER

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flags ¤Ë 0 ¤ò»ØÄꤷ¤¿¾ì¹ç¡¢²¿¤â¤·¤Ê¤¤¤³¤È¤òɽ¤¹¡£

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SYNC_FILE_RANGE_WAIT_BEFORE ¤È SYNC_FILE_RANGE_WAIT_AFTER ¤Ï I/O ¥¨¥é¡¼¤ä ENOSPC ¾õÂÖ¤ò¸¡½Ð¤·¡¢¸Æ¤Ó½Ð¤·¸µ¤Ë¤³¤ì¤é¤Î¾ðÊó¤òÊÖ¤¹¡£

flags ¤ÎÌò¤ËΩ¤Ä¥Ó¥Ã¥È¤ÎÁȤ߹ç¤ï¤»¤ò°Ê²¼¤Ë¼¨¤¹:

SYNC_FILE_RANGE_WAIT_BEFORE | SYNC_FILE_RANGE_WRITE

»ØÄꤵ¤ì¤¿ÈÏ°ÏÆâ¤Î¥Ú¡¼¥¸¤Ç¡¢ sync_file_range() ¤¬¸Æ¤Ó½Ð¤µ¤ì¤¿ºÝ¤Ë dirty ¤Ç¤¢¤Ã¤¿Á´¤Æ¤Î¥Ú¡¼¥¸¤¬¡¢ ³Î¼Â¤Ë½ñ¤­½Ð¤·ÂоݤȤʤë¤è¤¦¤Ë¤¹¤ë¡£ ¤³¤ì¤Ï¡¢start-write-for-data-integrity Áàºî (¥Ç¡¼¥¿´°Á´À­³ÎÊݤΤ¿¤á¤Î½ñ¤­¹þ¤ß³«»Ï¤ÎÁàºî) ¤Ç¤¢¤ë¡£

SYNC_FILE_RANGE_WRITE

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SYNC_FILE_RANGE_WAIT_BEFORE (or SYNC_FILE_RANGE_WAIT_AFTER)

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SYNC_FILE_RANGE_WAIT_BEFORE | SYNC_FILE_RANGE_WRITE | SYNC_FILE_RANGE_WAIT_AFTER

¤³¤ì¤Ï¡¢ÀΤ«¤é¤¢¤ë fdatasync(2) Áàºî¤½¤Î¤â¤Î¤Ç¤¢¤ë¡£ ¤³¤ì¤Ï write-for-data-integrity Áàºî (¥Ç¡¼¥¿´°Á´À­³ÎÊݤΤ¿¤á¤Î½ñ¤­¹þ¤ß) ¤Ç¤¢¤ê¡¢»ØÄꤵ¤ì¤¿ÈÏ°ÏÆâ¤Î¡¢ sync_file_range() ¤¬¸Æ¤Ð¤ì¤¿»þÅÀ¤Ç dirty ¤ÊÁ´¤Æ¤Î¥Ú¡¼¥¸¤¬ ¥Ç¥£¥¹¥¯¤Ë³ÊǼ¤µ¤ì¤ë¤³¤È¤¬Êݾڤµ¤ì¤ë¡£

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À®¸ù¤Î¾ì¹ç¡¢ sync_file_range() ¤Ï 0 ¤òÊÖ¤¹¡£¼ºÇԤξì¹ç¡¢-1 ¤òÊÖ¤·¡¢ error ¤Ë¥¨¥é¡¼¤ò¼¨¤¹ÃͤòÀßÄꤹ¤ë¡£

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EBADF

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

EIO

I/O ¥¨¥é¡¼¡£

EINVAL

flags ¤ËÉÔÀµ¤Ê¥Ó¥Ã¥È¤¬»ØÄꤵ¤ì¤Æ¤¤¤ë¡£¤Þ¤¿¤Ï offset ¤« nbytes ¤¬ÉÔÀµ¤Ç¤¢¤ë¡£

ENOMEM

¥á¥â¥êÉÔ­¤Ç¤¢¤ë¡£

ENOSPC

¥Ç¥£¥¹¥¯ÎΰèÉÔ­¤Ç¤¢¤ë¡£

ESPIPE

fd ¤¬¡¢Ä̾ï¤Î¥Õ¥¡¥¤¥ë¡¢¥Ö¥í¥Ã¥¯¥Ç¥Ð¥¤¥¹¡¢¥Ç¥£¥ì¥¯¥È¥ê¡¢¥·¥ó¥Ü¥ê¥Ã¥¯¥ê¥ó¥¯ °Ê³°¤Î¤â¤Î¤ò»Ø¤·¤Æ¤¤¤ë¡£

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sync_file_range() ¤Ï¥«¡¼¥Í¥ë 2.6.17 ¤Ç Linux ¤ËÅо줷¤¿¡£

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fdatasync(2), fsync(2), msync(2), sync(2), feature_test_macros(7)