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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN"><html><head><!-- Copyright 1997 The Open Group, All Rights Reserved --><title>&lt;sys/stat.h&gt;</title></head><body bgcolor=white><center><font size=2>The Single UNIX &reg; Specification, Version 2<br>Copyright &copy; 1997 The Open Group</font></center><hr size=2 noshade><h4><a name = "tag_000_009_348">&nbsp;</a>NAME</h4><blockquote>sys/stat.h - data returned by the<i><a href="stat.html">stat()</a></i>function</blockquote><h4><a name = "tag_000_009_349">&nbsp;</a>SYNOPSIS</h4><blockquote><pre><code>#include &lt;sys/stat.h&gt;</code></pre></blockquote><h4><a name = "tag_000_009_350">&nbsp;</a>DESCRIPTION</h4><blockquote>The<i>&lt;sys/stat.h&gt;</i>header defines the structure of the data returned by the functions<i><a href="fstat.html">fstat()</a></i>,<i><a href="lstat.html">lstat()</a></i>,and<i><a href="stat.html">stat()</a></i>.<p>The structure<b>stat</b>contains at least the following members:<pre><code>dev_t     st_dev     ID of device containing fileino_t     st_ino     file serial numbermode_t    st_mode    mode of file (see below)nlink_t   st_nlink   number of links to the fileuid_t     st_uid     user ID of filegid_t     st_gid     group ID of filedev_t     st_rdev    device ID (if file is character or block special)off_t     st_size    file size in bytes (if file is a regular file)time_t    st_atime   time of last accesstime_t    st_mtime   time of last data modificationtime_t    st_ctime   time of last status changeblksize_t st_blksize a filesystem-specific preferred I/O block size for                     this object.  In some filesystem types, this may                     vary from file to fileblkcnt_t  st_blocks  number of blocks allocated for this object</code></pre><p>File serial number and device ID taken together uniquelyidentify the file within the system.The<b>blkcnt_t</b>,<b>blksize_t</b>,<b>dev_t</b>,<b>ino_t</b>,<b>mode_t</b>,<b>nlink_t</b>,<b>uid_t</b>,<b>gid_t</b>,<b>off_t</b>and<b>time_t</b>types are defined as described in<i><a href="systypes.h.html">&lt;sys/types.h&gt;</a></i>.Times are given in seconds since the Epoch.<p>The following symbolic names for the values of st_modeare also defined:<p>File type:<dl compact><dt>S_IFMT<dd>type of file<dt>  S_IFBLK<dd>block special<dt>  S_IFCHR<dd>character special<dt>  S_IFIFO<dd>FIFO special<dt>  S_IFREG<dd>regular<dt>  S_IFDIR<dd>directory<dt>  S_IFLNK<dd>symbolic link</dl><p>File mode bits:<dl compact><dt>S_IRWXU<dd>read, write, execute/search by owner<dt>  S_IRUSR<dd>read permission, owner<dt>  S_IWUSR<dd>write permission, owner<dt>  S_IXUSR<dd>execute/search permission, owner<dt>S_IRWXG<dd>read, write, execute/search by group<dt>  S_IRGRP<dd>read permission, group<dt>  S_IWGRP<dd>write permission, group<dt>  S_IXGRP<dd>execute/search permission, group<dt>S_IRWXO<dd>read, write, execute/search by others<dt>  S_IROTH<dd>read permission, others<dt>  S_IWOTH<dd>write permission, others<dt>  S_IXOTH<dd>execute/search permission, others<dt>S_ISUID<dd>set-user-ID on execution<dt>S_ISGID<dd>set-group-ID on execution<dt>S_ISVTX<dd>on directories, restricted deletion flag</dl><p>The bits defined byS_IRUSR,S_IWUSR,S_IXUSR,S_IRGRP,S_IWGRP,S_IXGRP,S_IROTH,S_IWOTH,S_IXOTH,S_ISUID,S_ISGID&nbsp;and S_ISVTXare unique.<p>S_IRWXU is the bitwise OR ofS_IRUSR,S_IWUSR andS_IXUSR.<p>S_IRWXG is the bitwise OR ofS_IRGRP,S_IWGRP andS_IXGRP.<p>S_IRWXO is the bitwise OR ofS_IROTH,S_IWOTH andS_IXOTH.<p>Implementations may OR other implementation-dependent bits intoS_IRWXU,S_IRWXG andS_IRWXO, but they will not overlap any of the other bits definedin this document.The<i>file permission bits</i>are defined to be those corresponding to the bitwise inclusiveOR ofS_IRWXU,S_IRWXG andS_IRWXO.<p>The following macros will test whether a file is of thespecified type.The value<i>m</i>supplied to the macros is the value of<b>st_mode</b>from a<b>stat</b>structure.The macro evaluates to a non-zero value if the test is true,0 if the test is false.<dl compact><dt>S_ISBLK(<i>m</i>)<dd>Test for a block special file.<dt>S_ISCHR(<i>m</i>)<dd>Test for a character special file.<dt>S_ISDIR(<i>m</i>)<dd>Test for a directory.<dt>S_ISFIFO(<i>m</i>)<dd>Test for a pipe or FIFO special file.<dt>S_ISREG(<i>m</i>)<dd>Test for a regular file.<dt>S_ISLNK(<i>m</i>)<dd>Test for a symbolic link.</dl><p>The implementation may implementmessage queues, semaphores, or shared memory objectsas distinct file types.The following macros test whether a file is of the specifiedtype.The value of the<i>buf</i>argument supplied to the macros is a pointer to a<b>stat</b>structure.The macro evaluates to a non-zero valueif the specified object is implemented as a distinct file typeand the specified file type is contained in the<b>stat</b>structure referenced by<i>buf</i>.Otherwise, the macro evaluates to zero.<dl compact><dt>S_TYPEISMQ(<i>buf</i>)<dd>Test for a message queue<dt>S_TYPEISSEM(<i>buf</i>)<dd>Test for a semaphore<dt>S_TYPEISSHM(<i>buf</i>)<dd>Test for a shared memory object</dl><p>The following are declared as functions and may also be definedas macros.Function prototypes must be provided for use with an ISO Ccompiler.<pre><code>int    <a href="chmod.html">chmod</a>(const char *, mode_t);int    <a href="fchmod.html">fchmod</a>(int, mode_t);int    <a href="fstat.html">fstat</a>(int, struct stat *);int    <a href="lstat.html">lstat</a>(const char *, struct stat *);int    <a href="mkdir.html">mkdir</a>(const char *, mode_t);int    <a href="mkfifo.html">mkfifo</a>(const char *, mode_t);int    <a href="mknod.html">mknod</a>(const char *, mode_t, dev_t);int    <a href="stat.html">stat</a>(const char *, struct stat *);mode_t <a href="umask.html">umask</a>(mode_t);</code></pre></blockquote><h4><a name = "tag_000_009_351">&nbsp;</a>APPLICATION USAGE</h4><blockquote>Use of the macros is recommended for determining thetype of a file.</blockquote><h4><a name = "tag_000_009_352">&nbsp;</a>FUTURE DIRECTIONS</h4><blockquote>None.</blockquote><h4><a name = "tag_000_009_353">&nbsp;</a>SEE ALSO</h4><blockquote><i><a href="chmod.html">chmod()</a></i>,<i><a href="fchmod.html">fchmod()</a></i>,<i><a href="fstat.html">fstat()</a></i>,<i><a href="lstat.html">lstat()</a></i>,<i><a href="mkdir.html">mkdir()</a></i>,<i><a href="mkfifo.html">mkfifo()</a></i>,<i><a href="mknod.html">mknod()</a></i>,<i><a href="stat.html">stat()</a></i>,<i><a href="umask.html">umask()</a></i>,<i><a href="systypes.h.html">&lt;sys/types.h&gt;</a></i>.</blockquote><hr size=2 noshade><center><font size=2>UNIX &reg; is a registered Trademark of The Open Group.<br>Copyright &copy; 1997 The Open Group<br> [ <a href="../index.html">Main Index</a> | <a href="../xshix.html">XSH</a> | <a href="../xcuix.html">XCU</a> | <a href="../xbdix.html">XBD</a> | <a href="../cursesix.html">XCURSES</a> | <a href="../xnsix.html">XNS</a> ]</font></center><hr size=2 noshade></body></html>
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