[linuxjm/LDP_man-pages.git] / draft / man3 / ftw.3

.\" Copyright (c) 1993 Michael Haardt (u31b3hs@pool.informatik.rwth-aachen.de)
.\" and copyright (c) 1999 Andries Brouwer (aeb@cwi.nl)
.\" and copyright (c) 2006 Justin Pryzby <justinpryzby@users.sf.net>
.\" and copyright (c) 2006 Michael Kerrisk <mtk.manpages@gmail.com>
.\"
.\" This is free documentation; you can redistribute it and/or
.\" modify it under the terms of the GNU General Public License as
.\" published by the Free Software Foundation; either version 2 of
.\" the License, or (at your option) any later version.
.\"
.\" The GNU General Public License's references to "object code"
.\" and "executables" are to be interpreted as the output of any
.\" document formatting or typesetting system, including
.\" intermediate and printed output.
.\"
.\" This manual is distributed in the hope that it will be useful,
.\" but WITHOUT ANY WARRANTY; without even the implied warranty of
.\" MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
.\" GNU General Public License for more details.
.\"
.\" You should have received a copy of the GNU General Public
.\" License along with this manual; if not, write to the Free
.\" Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139,
.\" USA.
.\"
.\" Modified Sun Jul 25 11:02:22 1993 by Rik Faith (faith@cs.unc.edu)
.\" 2006-05-24, Justin Pryzby <justinpryzby@users.sf.net>
.\"     document FTW_ACTIONRETVAL; include .SH "RETURN VALUE";
.\" 2006-05-24, Justin Pryzby <justinpryzby@users.sf.net> and
.\"     Michael Kerrisk <mtk.manpages@gmail.com>
.\"     reorganized and rewrote much of the page
.\" 2006-05-24, Michael Kerrisk <mtk.manpages@gmail.com>
.\"     Added an example program.
.\"
.\" Japanese Version Copyright (c) 1998 NAKANO Takeo all rights reserved.
.\" Translated 1998-04-28, NAKANO Takeo <nakano@apm.seikei.ac.jp>
.\" Updated & Modified 1999-09-14, NAKANO Takeo <nakano@apm.seikei.ac.jp>
.\" Updated & Modified 2005-11-04, Akihiro MOTOKI <amotoki@dd.iij4u.or.jp>
.\" Updated 2006-07-26, Akihiro MOTOKI <amotoki@dd.iij4u.or.jp>, LDP v2.36
.\"
.\" WORD:       file descriptor         ¥Õ¥¡¥¤¥ë¥Ç¥£¥¹¥¯¥ê¥×¥¿¡¼
.\"
.TH FTW 3 2010-09-20 "Linux" "Linux Programmer's Manual"
.\"O .SH NAME
.SH ̾Á°
.\"O ftw, nftw \- file tree walk
ftw, nftw \- ¥Õ¥¡¥¤¥ë¥Ä¥ê¡¼¤òÊ⤭¤Þ¤ï¤ë
.\"O .SH SYNOPSIS
.SH ½ñ¼°
.nf
.B #include <ftw.h>
.sp
.BI "int ftw(const char *" dirpath ,
.BI "        int (*" fn ") (const char *" fpath ", const struct stat *" sb ,
.BI "                   int " typeflag ),
.BI "        int " nopenfd );
.sp
.B #define _XOPEN_SOURCE 500
.B #include <ftw.h>
.sp
.BI "int nftw(const char *" dirpath ,
.BI "        int (*" fn ") (const char *" fpath ", const struct stat *" sb ,
.BI "                   int " typeflag ", struct FTW *" ftwbuf ),
.BI "        int " nopenfd ", int " flags );
.fi
.\"O .SH DESCRIPTION
.SH ÀâÌÀ
.\"O .BR ftw ()
.\"O walks through the directory tree that is
.\"O located under the directory \fIdirpath\fP,
.\"O and calls \fIfn\fP() once for each entry in the tree.
.\"O By default, directories are handled before the files and
.\"O subdirectories they contain (preorder traversal).
.BR ftw ()
¤Ï¡¢
.I dirpath
¤Ç»ØÄꤵ¤ì¤¿¥Ç¥£¥ì¥¯¥È¥ê°Ê²¼¤Î¥Ç¥£¥ì¥¯¥È¥ê¥Ä¥ê¡¼Á´ÂΤòÊ⤭¤Þ¤ï¤ê¡¢
¥Ä¥ê¡¼Ãæ¤Ç¥¨¥ó¥È¥ê¤¬¸«ÉÕ¤«¤ë¤´¤È¤Ë¡¢
.IR fn ()
¤ò¸Æ¤Ó½Ð¤¹¡£
¥Ç¥Õ¥©¥ë¥È¤Ç¤Ï¡¢¥Ç¥£¥ì¥¯¥È¥ê¤½¤Î¤â¤Î¤¬¡¢¤½¤Î¥Ç¥£¥ì¥¯¥È¥ê¤Ë¤¢¤ë¥Õ¥¡¥¤¥ë¤ä
¥µ¥Ö¥Ç¥£¥ì¥¯¥È¥ê¤è¤ê¤âÀè¤Ë½èÍý¤µ¤ì¤ë (¹Ô¤­¤¬¤±½çõº÷; preorder traversal)¡£

.\"O To avoid using up all of the calling process's file descriptors,
.\"O \fInopenfd\fP specifies the maximum number of directories that
.\"O .BR ftw ()
.\"O will hold open simultaneously.
.\"O When
.\"O the search depth exceeds this,
.\"O .BR ftw ()
.\"O will become slower because
.\"O directories have to be closed and reopened.
.\"O .BR ftw ()
.\"O uses at most
.\"O one file descriptor for each level in the directory tree.
¸Æ¤Ó½Ð¤·¸µ¥×¥í¥»¥¹¤¬ÍøÍѲÄǽ¤Ê¥Õ¥¡¥¤¥ë¥Ç¥£¥¹¥¯¥ê¥×¥¿¤ò»È¤¤ÀڤäÆ
¤·¤Þ¤ï¤Ê¤¤¤è¤¦¤Ë¤¹¤ë¤¿¤á¡¢
.BR ftw ()
¤¬Æ±»þ¤Ë¥ª¡¼¥×¥ó¤¹¤ë¥Ç¥£¥ì¥¯¥È¥ê¤ÎºÇÂç¿ô¤ò
.I nopenfd
¤Ç»ØÄꤹ¤ë¤³¤È¤¬¤Ç¤­¤ë¡£
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°ì¤Ä¤Î¥Ç¥£¥ì¥¯¥È¥ê¤òÊĤ¸¤Æ¤«¤é¾¤Î¥Ç¥£¥ì¥¯¥È¥ê¤ò¥ª¡¼¥×¥ó¤·Ä¾¤¹¤³¤È
¤Ë¤Ê¤ë¤Î¤Ç¡¢
.BR ftw ()
¤ÎÆ°ºî¤ÏÃÙ¤¯¤Ê¤ë¡£
.BR ftw ()
¤Ï¡¢¥Ç¥£¥ì¥¯¥È¥ê¥Ä¥ê¡¼¤Î³¬ÁØ 1 ¥ì¥Ù¥ë¤Ë¤Ä¤­¡¢
ºÇÂç¤Ç¤â°ì¤Ä¤Î¥Õ¥¡¥¤¥ë¥Ç¥£¥¹¥¯¥ê¥×¥¿¤·¤«»ÈÍѤ·¤Ê¤¤¡£

.\"O For each entry found in the tree,
.\"O .BR ftw ()
.\"O calls
.\"O \fIfn\fP() with three arguments:
.\"O .IR fpath ,
.\"O .IR sb ,
.\"O and
.\"O .IR typeflag .
¥Ç¥£¥ì¥¯¥È¥ê¥Ä¥ê¡¼¤Ç¸«¤Ä¤«¤Ã¤¿¥¨¥ó¥È¥êËè¤Ë¡¢
.BR ftw ()
¤Ï
.IR fpath ,
.IR sb ,
.I typeflag
¤Î 3¤Ä¤ò°ú¤­¿ô¤È¤·¤Æ
.IR fn ()
¤ò¸Æ¤Ó½Ð¤¹¡£
.\"O .I fpath
.\"O is the pathname of the entry,
.\"O and is expressed either as a pathname relative to the calling process's
.\"O current working directory at the time of the call to
.\"O .BR ftw (),
.\"O if
.\"O .IR dirpath
.\"O was expressed as a relative pathname,
.\"O or as an absolute pathname, if
.\"O .I dirpath
.\"O was expressed as an absolute pathname.
.I fpath
¤Ï¥¨¥ó¥È¥ê¤Î¥Ñ¥¹Ì¾¤Ç¤¢¤ë¡£
.I dirpath
¤¬ÁêÂХѥ¹Ì¾¤Ç»ØÄꤵ¤ì¤¿¾ì¹ç¤Ë¤Ï¡¢
.I fpath
¤Ï
.BR ftw ()
¤¬¸Æ¤Ó½Ð¤µ¤ì¤¿»þÅÀ¤Î¸Æ¤Ó½Ð¤·¸µ¥×¥í¥»¥¹¤Î¥«¥ì¥ó¥È¥ï¡¼¥­¥ó¥°¥Ç¥£¥ì¥¯¥È¥ê
¤«¤é¤ÎÁêÂХѥ¹Ì¾¤È¤Ê¤ë¡£
.I dirpath
¤¬ÀäÂХѥ¹Ì¾¤Ç»ØÄꤵ¤ì¤¿¾ì¹ç¤Ë¤Ï¡¢
.I fpath
¤ÏÀäÂХѥ¹Ì¾¤È¤Ê¤ë¡£
.\"O .I sb
.\"O is a pointer to the
.\"O .I stat
.\"O structure returned by a call to
.\"O .BR stat (2)
.\"O for
.\"O .IR fpath .
.I sb
¤Ï
.I fpath
¤ËÂФ¹¤ë
.BR stat (2)
¤Î¸Æ¤Ó½Ð¤·¤ÇÊÖ¤µ¤ì¤ë
.I stat
¹½Â¤ÂΤؤΥݥ¤¥ó¥¿¤Ç¤¢¤ë¡£
.\"O .I typeflag
.\"O is an integer that has one of the following values:
.I typeflag
¤ÏÀ°¿ô¤Ç¡¢°Ê²¼¤ÎÃͤΤ¤¤º¤ì¤«°ì¤Ä¤Ç¤¢¤ë:
.TP
.B FTW_F
.\"O .I fpath
.\"O is a regular file.
.I fpath
¤¬Ä̾ï¤Î¥Õ¥¡¥¤¥ë¤Ç¤¢¤ë
.TP
.B FTW_D
.\"O .I fpath
.\"O is a directory.
.I fpath
¤¬¥Ç¥£¥ì¥¯¥È¥ê¤Ç¤¢¤ë
.TP
.B FTW_DNR
.\"O .I fpath
.\"O is a directory which can't be read.
.I fpath
¤¬Æɤ߹þ¤ß¤Ç¤­¤Ê¤¤¥Ç¥£¥ì¥¯¥È¥ê¤Ç¤¢¤ë
.TP
.B FTW_NS
.\"O The
.\"O .BR stat (2)
.\"O call failed on
.\"O .IR fpath ,
.\"O which is not a symbolic link.
¥·¥ó¥Ü¥ê¥Ã¥¯¥ê¥ó¥¯¤Ç¤Ï¤Ê¤¤
.I fpath
¤ËÂФ¹¤ë
.BR stat (2)
¸Æ¤Ó½Ð¤·¤¬¼ºÇÔ¤·¤¿¡£
.sp
.\"O If
.\"O .I fpath
.\"O is a symbolic link and
.\"O .BR stat (2)
.\"O failed, POSIX.1-2001 states
.\"O that it is undefined whether \fBFTW_NS\fP or \fBFTW_SL\fP (see below)
.\"O is passed in
.\"O .IR typeflag .
.I fpath
¤¬¥·¥ó¥Ü¥ê¥Ã¥¯¥ê¥ó¥¯¤Ç¡¢¤«¤Ä
.BR stat (2)
¤¬¼ºÇÔ¤·¤¿¾ì¹ç¡¢
.B FTW_NS
¤È
.B FTW_SL
(¸å½Ò) ¤Î¤É¤Á¤é¤¬
.I typeflag
¤ËÅϤµ¤ì¤ë¤«¤Ï̤ÄêµÁ¤Ç¤¢¤ë¤È¡¢POSIX.1-2001 ¤Ë¤Ï½ñ¤«¤ì¤Æ¤¤¤ë¡£
.PP
.\"O To stop the tree walk, \fIfn\fP() returns a nonzero value; this
.\"O value will become the return value of
.\"O .BR ftw ().
.\"O As long as \fIfn\fP() returns 0,
.\"O .BR ftw ()
.\"O will continue either until it has traversed the entire tree,
.\"O in which case it will return zero,
.\"O or until it encounters an error (such as a
.\"O .BR malloc (3)
.\"O failure), in which case it will return \-1.
¥Ä¥ê¡¼¤Îõº÷¤ò»ß¤á¤¿¤¤¾ì¹ç¤Ï¡¢
.IR fn ()
¤¬ 0 °Ê³°¤ÎÃͤòÊÖ¤»¤ÐÎɤ¤
(¤³¤ÎÃͤÏ
.BR ftw ()
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¤½¤ì°Ê³°¤Î¾ì¹ç¤Ï
.BR ftw ()
¤Ï¥Ä¥ê¡¼Á´ÂΤÎõº÷¤ò³¤±¡¢¤¹¤Ù¤Æ¤Î¥Ä¥ê¡¼¤òõº÷¤·½ª¤¨¤¿¤È¤³¤í¤Ç
0 ¤òÊÖ¤¹¡£Ãµº÷Ãæ¤Ë
.RB ( malloc (3)
¤Î¼ºÇԤʤɤÎ) ¥¨¥é¡¼¤¬µ¯¤³¤ë¤È \-1 ¤òÊÖ¤¹¡£
.PP
.\"O Because
.\"O .BR ftw ()
.\"O uses dynamic data structures, the only safe way to
.\"O exit out of a tree walk is to return a nonzero value from \fIfn\fP().
.\"O To allow a signal to terminate the walk without causing a memory leak,
.\"O have the handler set a global flag that is checked by \fIfn\fP().
.\"O \fIDon't\fP use
.\"O .BR longjmp (3)
.\"O unless the program is going to terminate.
.BR ftw ()
¤ÏưŪ¤Ê¥Ç¡¼¥¿¹½Â¤¤òÍѤ¤¤ë¤Î¤Ç¡¢¥Ä¥ê¡¼Ãµº÷¤ò°ÂÁ´¤ËÃæÃǤ¹¤ëÍ£°ì¤ÎÊýË¡¤Ï
0 °Ê³°¤ÎÃͤò
.IR fn ()
¤ÎÊÖ¤êÃͤȤ¹¤ë¤³¤È¤Ç¤¢¤ë¡£³ä¤ê¹þ¤ß¤ò°·¤¦¤Ë¤Ï¡¢
Î㤨¤ÐȯÀ¸¤·¤¿³ä¤ê¹þ¤ß¤ò¥Þ¡¼¥¯¤·¤Æ¤ª¤¤¤Æ¡¢ 0 °Ê³°¤ÎÃͤòÊÖ¤¹¤è¤¦¤Ë¤¹¤ë
¥·¥°¥Ê¥ë¤Ë¤è¤ê¥á¥â¥ê¥ê¡¼¥¯¤òµ¯¤³¤µ¤º¤Ëõº÷¤ò½ªÎ»¤Ç¤­¤ë¤è¤¦¤Ë¤¹¤ë¤Ë¤Ï¡¢
¥·¥°¥Ê¥ë¥Ï¥ó¥É¥é¤Ç
.IR fn ()
¤¬¥Á¥§¥Ã¥¯¤¹¤ë¥°¥í¡¼¥Ð¥ë¤Ê¥Õ¥é¥°¤ò¥»¥Ã¥È¤¹¤ë¤è¤¦¤Ë¤¹¤ì¤Ð¤è¤¤¡£
¥×¥í¥°¥é¥à¤ò½ªÎ»¤µ¤»¤ë¾ì¹ç°Ê³°¤Ï¡¢
.BR longjmp (3)
¤ò»ÈÍѤ·¤Ê¤¤¤³¤È¡£
.SS nftw()
.\"O The function \fBnftw\fP() is the same as
.\"O .BR ftw (),
.\"O except that it has one additional argument, \fIflags\fP,
.\"O and calls \fIfn\fP() with one more argument, \fIftwbuf\fP.
´Ø¿ô
.BR nftw ()
¤Ï
.BR ftw ()
¤ÈƱ¤¸¤À¤¬¡¢°ú¤­¿ô
.I flags
¤¬Äɲ䵤ì¤ëÅÀ¤È¡¢
.IR fn ()
¤Î°ú¤­¿ô¤Ë
.I ftwbuf
¤¬Äɲ䵤ì¤ëÅÀ¤¬°Û¤Ê¤ë¡£

.\"O This \fIflags\fP argument is formed by ORing zero or more of the
.\"O following flags:
¤³¤Î
.I flags
°ú¤­¿ô¤Ï²¼µ­¤Î¥Õ¥é¥°¤Î 0 ¸Ä°Ê¾å¤ÎÏÀÍýϤò¼è¤Ã¤¿¤â¤Î¤Ç¤¢¤ë:
.TP
.\"O .BR FTW_ACTIONRETVAL " (since glibc 2.3.3)"
.BR FTW_ACTIONRETVAL " (glibc 2.3.3 °Ê¹ß)"
.\"O If this glibc-specific flag is set, then
.\"O .BR nftw ()
.\"O handles the return value from
.\"O .IR fn ()
.\"O differently.
.\"O .IR fn ()
.\"O should return one of the following values:
¤³¤Î¥Õ¥é¥°¤Ï glibc ¸ÇÍ­¤Ç¤¢¤ë¡£
¤³¤Î¥Õ¥é¥°¤ò¥»¥Ã¥È¤¹¤ë¤È¡¢
.BR nftw ()
¤Î
.IR fn ()
¤ÎÊÖ¤êÃͤΰ·¤¤¤¬ÊѤï¤ë¡£
.IR fn ()
¤Ï°Ê²¼¤ÎÃͤΤ¤¤º¤ì¤«°ì¤Ä¤òÊÖ¤¹É¬Íפ¬¤¢¤ë¡£
.RS
.TP
.B FTW_CONTINUE
.\"O Instructs
.\"O .BR nftw ()
.\"O to continue normally.
.BR nftw ()
¤ÏÄ̾ïÄ̤ê½èÍý¤ò³¤±¤ë¡£
.TP
.B FTW_SKIP_SIBLINGS
.\"O If \fIfn\fP() returns this value, then
.\"O siblings of the current entry will be skipped,
.\"O and processing continues in the parent.
.IR fn ()
¤¬¤³¤ÎÃͤòÊÖ¤·¤¿¾ì¹ç¡¢½èÍýÃæ¤Î¥¨¥ó¥È¥ê¤Î·»Äï (Ʊ¤¸³¬ÁؤΥ¨¥ó¥È¥ê)
¤Î½èÍý¤Ï¥¹¥­¥Ã¥×¤µ¤ì¡¢¿Æ¥Ç¥£¥ì¥¯¥È¥ê¤Ç³¤­¤Î½èÍý¤¬¹Ô¤ï¤ì¤ë¡£
.\" If \fBFTW_DEPTH\fP
.\" is set, the entry's parent directory is processed next (with
.\" \fIflag\fP set to \fBFTW_DP\fP).
.TP
.B FTW_SKIP_SUBTREE
.\"O If \fIfn\fP() is called with an entry that is a directory
.\"O (\fItypeflag\fP is \fBFTW_D\fP), this return
.\"O value will prevent objects within that directory from being passed as
.\"O arguments to \fIfn\fP().
.\"O .BR nftw ()
.\"O continues processing with the next sibling of the directory.
.IR fn ()
¤¬¸Æ¤Ó½Ð¤µ¤ì¤¿¥¨¥ó¥È¥ê¤¬¥Ç¥£¥ì¥¯¥È¥ê
.RI ( typeflag
¤¬
.BR FTW_D )
¤Î¾ì¹ç¤Ë¡¢¤³¤ÎÃͤòÊÖ¤¹¤È
.IR fn ()
¤Î°ú¤­¿ô¤È¤·¤ÆÅϤµ¤ì¤¿¥Ç¥£¥ì¥¯¥È¥êÆâ¤Î¥¨¥ó¥È¥ê¤Î½èÍý¤¬¹Ô¤ï¤ì¤Ê¤¯¤Ê¤ë¡£
.BR nftw ()
¤Ï½èÍýÃæ¤Î¥Ç¥£¥ì¥¯¥È¥ê¤Î·»Äï (Ʊ¤¸³¬ÁؤΥ¨¥ó¥È¥ê) ¤«¤é½èÍý¤ò³¤±¤ë¡£
.TP
.B FTW_STOP
.\"O Causes
.\"O .BR nftw ()
.\"O to return immediately with the return value
.\"O \fBFTW_STOP\fP.
.B nftw ()
¤Ï¡¢ÊÖ¤êÃÍ
.B FTW_STOP
¤Ç¤¹¤°¤ËÉüµ¢¤¹¤ë¡£
.PP
.\"O Other return values could be associated with new actions in the future;
.\"O \fIfn\fP() should not return values other than those listed above.
¾¤ÎÊÖ¤êÃͤϾ­Íè¿·¤·¤¤Æ°ºî¤ËÂбþÉÕ¤±¤é¤ì¤ë²ÄǽÀ­¤¬¤¢¤ë¡£
.IR fn ()
¤Ï¾åµ­¤Î¥ê¥¹¥È¤Ë¤¢¤ëÃͰʳ°¤òÊÖ¤µ¤Ê¤¤¤è¤¦¤Ë¤¹¤Ù¤­¤Ç¤¢¤ë¡£

.\"O The feature test macro
.\"O .B _GNU_SOURCE
.\"O must be defined
.\"O (before including
.\"O .I any
.\"O header files)
.\"O in order to
.\"O obtain the definition of \fBFTW_ACTIONRETVAL\fP from \fI<ftw.h>\fP.
.I <ftw.h>
¤Ç
.B FTW_ACTIONRETVAL
¤ÎÄêµÁ¤¬Í­¸ú¤Ë¤¹¤ë¤¿¤á¤Ë¤Ï¡¢
(¡Ö¤É¤Î¡×¥Ø¥Ã¥À¥Õ¥¡¥¤¥ë¤ò¥¤¥ó¥¯¥ë¡¼¥É¤¹¤ë¤è¤ê¤âÁ°¤Ë)
µ¡Ç½¸¡ºº¥Þ¥¯¥í
.B _GNU_SOURCE
¤òÄêµÁ¤·¤Ê¤±¤ì¤Ð¤Ê¤é¤Ê¤¤¡£
.RE
.TP
.B FTW_CHDIR
.\"O If set, do a
.\"O .BR chdir (2)
.\"O to each directory before handling its contents.
.\"O This is useful if the program needs to perform some action
.\"O in the directory in which \fIfpath\fP resides.
¥»¥Ã¥È¤µ¤ì¤ë¤È¡¢¥Ç¥£¥ì¥¯¥È¥ê¤ÎÆâÍƤò½èÍý¤¹¤ëÁ°¤Ë
¤½¤Î¥Ç¥£¥ì¥¯¥È¥ê¤Ë
.BR chdir (2)
¤¹¤ë¡£¤³¤Î¥Õ¥é¥°¤Ï¡¢
.I fpath
¤¬Â°¤¹¥Ç¥£¥ì¥¯¥È¥ê¤Ç²¿¤é¤«¤ÎÆ°ºî¤ò¼Â¹Ô¤¹¤ëɬÍפ¬¤¢¤ë¾ì¹ç¤Ë
ÊØÍø¤Ç¤¢¤ë¡£
.TP
.B FTW_DEPTH
.\"O If set, do a post-order traversal, that is, call \fIfn\fP() for
.\"O the directory itself \fIafter\fP handling the contents of the directory
.\"O and its subdirectories.
.\"O (By default, each directory is handled \fIbefore\fP its contents.)
¥»¥Ã¥È¤µ¤ì¤ë¤È¡¢µ¢¤ê¤¬¤±½çõº÷ (post-order traversal) ¤ò¹Ô¤¦¡£
¤Ä¤Þ¤ê¡¢¥Ç¥£¥ì¥¯¥È¥ê¤½¤Î¤â¤Î¤ò°ú¤­¿ô¤È¤·¤¿
.IR fn ()
¸Æ½Ð¤·¤Ï¡¢¤½¤Î¥Ç¥£¥ì¥¯¥È¥ê¤Ë´Þ¤Þ¤ì¤ë¥Õ¥¡¥¤¥ë¤È¥µ¥Ö¥Ç¥£¥ì¥¯¥È¥ê¤Ë
ÂФ¹¤ë½èÍý¤Î¡Ö¸å¤Ç¡×¹Ô¤ï¤ì¤ë
(¥Ç¥Õ¥©¥ë¥È¤Ç¤Ï¡¢¥Ç¥£¥ì¥¯¥È¥ê¼«¿È¤Î½èÍý¤Ï¥Ç¥£¥ì¥¯¥È¥êÆâ¤Î¥¨¥ó¥È¥ê
¤è¤ê¡ÖÁ°¤Ë¡×¹Ô¤Ê¤ï¤ì¤ë)¡£
.TP
.B FTW_MOUNT
.\"O If set, stay within the same file system
.\"O (i.e., do not cross mount points).
¥»¥Ã¥È¤µ¤ì¤ë¤È¡¢Æ±¤¸¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤ÎÃæ¤À¤±¤òõº÷ÂоݤȤ¹¤ë
(¤Ä¤Þ¤ê¡¢¥Þ¥¦¥ó¥È¥Ý¥¤¥ó¥È¤ò¤Þ¤¿¤°¤³¤È¤Ï¤Ê¤¤)¡£
.TP
.B FTW_PHYS
.\"O If set, do not follow symbolic links.
.\"O (This is what you want.)
.\"O If not set, symbolic links are followed, but no file is reported twice.
¥»¥Ã¥È¤µ¤ì¤ë¤È¡¢¥·¥ó¥Ü¥ê¥Ã¥¯¥ê¥ó¥¯¤òé¤é¤Ê¤¤ (¤ª¤½¤é¤¯¤³¤Á¤é¤¬
Ä̾ï˾¤Þ¤·¤¤Æ°ºî¤À¤í¤¦)¡£¥»¥Ã¥È¤µ¤ì¤Æ¤¤¤Ê¤¤¤È¥·¥ó¥Ü¥ê¥Ã¥¯¥ê¥ó¥¯¤ò
é¤ë¤¬¡¢Æ±¤¸¥Õ¥¡¥¤¥ë¤¬Æó²óÊó¹ð¤µ¤ì¤ë¤³¤È¤Ï¤Ê¤¤¡£
.sp
.\"O If \fBFTW_PHYS\fP is not set, but \fBFTW_DEPTH\fP is set,
.\"O then the function
.\"O .IR fn ()
.\"O is never called for a directory that would be a descendant of itself.
.B FTW_PHYS
¤¬¥»¥Ã¥È¤µ¤ì¤º¤Ë
.B FTW_DEPTH
¤¬¥»¥Ã¥È¤µ¤ì¤ë¤È¡¢¼«Ê¬¼«¿È¤ËÂФ¹¤ë¥·¥ó¥Ü¥ê¥Ã¥¯¥ê¥ó¥¯¤òÇÛ²¼¤Ë»ý¤Ä
¥Ç¥£¥ì¥¯¥È¥ê¤ËÂФ·¤Æ
.IR fn ()
¤¬¸Æ¤Ó½Ð¤µ¤ì¤ë¤³¤È¤Ï·è¤·¤Æ¤Ê¤¤¡£
.LP
.\"O For each entry in the directory tree,
.\"O .BR nftw ()
.\"O calls
.\"O .IR fn ()
.\"O with four arguments.
.\"O .I fpath
.\"O and
.\"O .I sb
.\"O are as for
.\"O .BR ftw ().
.\"O .I typeflag
.\"O may receive any of the same values as with
.\"O .BR ftw (),
.\"O or any of the following values:
¥Ç¥£¥ì¥¯¥È¥ê¥Ä¥ê¡¼¤Î¥¨¥ó¥È¥êËè¤Ë¡¢
.BR nftw ()
¤Ï 4¤Ä¤Î°ú¤­¿ô¤Ç
.IR fn ()
¤ò¸Æ¤Ó½Ð¤¹¡£
.I fpath
¤È
.I sb
¤Ï
.BR ftw ()
¤ÈƱ¤¸¤Ç¤¢¤ë¡£
.I typeflag
¤Ë¤Ï¡¢
.BR ftw ()
¤Ç¼è¤êÆÀ¤ëÃͤΤ¤¤º¤ì¤«¡¢¤Þ¤¿¤Ï°Ê²¼¤ÎÃͤΤ¤¤º¤ì¤«¤¬ÅϤµ¤ì¤ë:
.TP
.B FTW_DP
.\"O .I fpath
.\"O is a directory, and \fBFTW_DEPTH\fP was specified in \fIflags\fP.
.\"O All of the files
.\"O and subdirectories within \fIfpath\fP have been processed.
.I fpath
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.I flags
¤Ç
.B FTW_DEPTH
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.I fpath
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.TP
.B FTW_SL
.\"O .I fpath
.\"O is a symbolic link, and \fBFTW_PHYS\fP was set in \fIflags\fP.
.I fpath
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.\" To obtain the definition of this constant from
.\" .IR <ftw.h> ,
.\" either
.\" .B _BSD_SOURCE
.\" must be defined, or
.\" .BR _XOPEN_SOURCE
.\" must be defined with a value of 500 or more.
.TP
.B FTW_SLN
.\"O .I fpath
.\"O is a symbolic link pointing to a nonexistent file.
.\"O (This occurs only if \fBFTW_PHYS\fP is not set.)
.I fpath
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(¤³¤ì¤¬¥»¥Ã¥È¤µ¤ì¤ë¤Î¤Ï
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.LP
.\"O The fourth argument that
.\"O .BR nftw ()
.\"O supplies when calling
.\"O \fIfn\fP()
.\"O is a structure of type \fIFTW\fP:
.BR nftw ()
¤¬
.IR fn ()
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.I FTW
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.in +4n
.nf

struct FTW {
    int base;
    int level;
};

.fi
.in
.\"O .I base
.\"O is the offset of the filename (i.e., basename component)
.\"O in the pathname given in
.\"O .IR fpath .
.\"O .I level
.\"O is the depth of
.\"O .I fpath
.\"O in the directory tree, relative to the root of the tree
.\"O .RI ( dirpath ,
.\"O which has depth 0).
.I base
¤Ï¡¢¥Õ¥¡¥¤¥ë̾ (basename Í×ÁÇ) ¤Î¡¢
.I fpath
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.I level
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.I fpath
¤Î¿¼¤µ¤ò¼¨¤¹¡£¿¼¤µ¤Ï¥Ç¥£¥ì¥¯¥È¥ê¥Ä¥ê¡¼¤Î¥È¥Ã¥× (root) ¤«¤é¤Î
ÁêÂÐÃͤǤ¢¤ë
.RI ( dirpath
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.\"O .SH "RETURN VALUE"
.SH ÊÖ¤êÃÍ
.\"O These functions return 0 on success, and \-1 if an error occurs.
¤³¤ì¤é¤Î´Ø¿ô¤Ï¡¢À®¸ù¤¹¤ë¤È 0 ¤ò¡¢¥¨¥é¡¼¤¬È¯À¸¤¹¤ë¤È \-1 ¤òÊÖ¤¹¡£

.\"O If \fIfn\fP() returns nonzero,
.\"O then the tree walk is terminated and the value returned by \fIfn\fP()
.\"O is returned as the result of \fBftw\fP() or
.\"O .BR nftw ().
.IR fn ()
¤¬ 0 °Ê³°¤òÊÖ¤·¤¿¾ì¹ç¡¢¥Ç¥£¥ì¥¯¥È¥ê¥Ä¥ê¡¼¤Îõº÷¤ò½ªÎ»¤·¡¢
.IR fn ()
¤¬ÊÖ¤·¤¿Ãͤò
.BR ftw ()
¤ä
.BR nftw ()
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.\"O If
.\"O .BR nftw ()
.\"O is called with the \fBFTW_ACTIONRETVAL\fP flag,
.\"O then the only nonzero value that should be used by \fIfn\fP()
.\"O to terminate the tree walk is \fBFTW_STOP\fP,
.\"O and that value is returned as the result of
.\"O .BR nftw ().
.BR nftw ()
¤¬
.B FTW_ACTIONRETVAL
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.IR fn ()
¤¬»ÈÍѤǤ­¤ë¡¢Èó 0 ¤ÎÃͤÏ
.B FTW_STOP
¤À¤±¤Ç¤¢¤ê¡¢
¤³¤ÎÃͤÏ
.BR nftw ()
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.\"O .SH "CONFORMING TO"
.SH ½àµò
POSIX.1-2001, SVr4, SUSv1.
.\"O POSIX.1-2008 marks
.\"O .BR ftw ()
.\"O as obsolete.
POSIX.1-2008 ¤Ï
.BR ftw ()
¤òÇÑ»ßͽÄê¤È¤·¤Æ¤¤¤ë¡£
.\"O .SH NOTES
.SH Ãí°Õ
.\"O POSIX.1-2001 note that the results are unspecified if
.\"O .I fn
.\"O does not preserve the current working directory.
POSIX.1-2001 ¤ÎÃíµ­¤Ë¤è¤ë¤È¡¢
.I fn
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.PP
.\"O The function
.\"O .BR nftw ()
.\"O and the use of \fBFTW_SL\fP with
.\"O .BR ftw ()
.\"O were introduced in SUSv1.
.BR nftw ()
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.BR ftw ()
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.LP
.\"O On some systems
.\"O .BR ftw ()
.\"O will never use \fBFTW_SL\fP, on other systems \fBFTW_SL\fP occurs only
.\"O for symbolic links that do not point to an existing file,
.\"O and again on other systems
.\"O .BR ftw ()
.\"O will use \fBFTW_SL\fP for each symbolic link.
.\"O For predictable control, use
.\"O .BR nftw ().
.BR ftw ()
¤Ç
.B FTW_SL
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.B FTW_SL
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.BR ftw ()
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.B FTW_SL
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.BR nftw ()
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.\"O Under Linux, libc4 and libc5 and glibc 2.0.6 will
.\"O use \fBFTW_F\fP for all objects (files, symbolic links, FIFOs, etc.)
.\"O that can be stat'ed but are not a directory.
Linux ¤Ç¤Ï¡¢ libc4, libc5, glibc 2.0.6 ¤Ï
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(¥Õ¥¡¥¤¥ë, ¥·¥ó¥Ü¥ê¥Ã¥¯¥ê¥ó¥¯, fifo Åù)
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.\"O The function
.\"O .BR nftw ()
.\"O is available since glibc 2.1.
.BR nftw ()
´Ø¿ô¤Ï glibc 2.1 °Ê¹ß¤ÇÍøÍѤǤ­¤ë¡£

.\"O \fBFTW_ACTIONRETVAL\fP is glibc-specific.
.B FTW_ACTIONRETVAL
¤Ï glibc ¸ÇÍ­¤Ç¤¢¤ë¡£
.\"O .SH EXAMPLE
.SH Îã
.\"O The following program traverses the directory tree under the path named
.\"O in its first command-line argument, or under the current directory
.\"O if no argument is supplied.
.\"O It displays various information about each file.
.\"O The second command-line argument can be used to specify characters that
.\"O control the value assigned to the \fIflags\fP
.\"O argument when calling
.\"O .BR nftw ().
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³Æ¡¹¤Î¥Õ¥¡¥¤¥ë¤Ë¤Ä¤¤¤ÆÍÍ¡¹¤Î¾ðÊó¤¬É½¼¨¤µ¤ì¤ë¡£
ÆóÈÖÌܤΥ³¥Þ¥ó¥É¥é¥¤¥ó°ú¤­¿ô¤Ëʸ»ú¤ò»ØÄꤹ¤ë¤³¤È¤Ç¡¢
.BR nftw ()
¤ò¸Æ¤Ó½Ð¤¹ºÝ¤Ë
.I flags
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.nf

#define _XOPEN_SOURCE 500
#include <ftw.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdint.h>

static int
display_info(const char *fpath, const struct stat *sb,
             int tflag, struct FTW *ftwbuf)
{
    printf("%\-3s %2d %7jd   %\-40s %d %s\\n",
        (tflag == FTW_D) ?   "d"   : (tflag == FTW_DNR) ? "dnr" :
        (tflag == FTW_DP) ?  "dp"  : (tflag == FTW_F) ?   "f" :
        (tflag == FTW_NS) ?  "ns"  : (tflag == FTW_SL) ?  "sl" :
        (tflag == FTW_SLN) ? "sln" : "???",
        ftwbuf\->level, (intmax_t) sb\->st_size,
        fpath, ftwbuf\->base, fpath + ftwbuf\->base);
    return 0;           /* To tell nftw() to continue */
}

int
main(int argc, char *argv[])
{
    int flags = 0;

    if (argc > 2 && strchr(argv[2], \(aqd\(aq) != NULL)
        flags |= FTW_DEPTH;
    if (argc > 2 && strchr(argv[2], \(aqp\(aq) != NULL)
        flags |= FTW_PHYS;

    if (nftw((argc < 2) ? "." : argv[1], display_info, 20, flags)
            == \-1) {
        perror("nftw");
        exit(EXIT_FAILURE);
    }
    exit(EXIT_SUCCESS);
}
.fi
.\"O .SH "SEE ALSO"
.SH ´ØÏ¢¹àÌÜ
.BR stat (2),
.BR fts (3),
.BR readdir (3),
.BR feature_test_macros (7)