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<H1>stat(2)</H1>
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<H2>NAME</H2><PRE>
stat, lstat, fstat - get file status
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<H2>SYNOPSIS</H2><PRE>
<STRONG>#include</STRONG> <STRONG>&lt;sys/types.h&gt;</STRONG>
<STRONG>#include</STRONG> <STRONG>&lt;sys/stat.h&gt;</STRONG>
<STRONG>int</STRONG> <STRONG>stat(const</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG><EM>path</EM><STRONG>,</STRONG> <STRONG>struct</STRONG> <STRONG>stat</STRONG> <STRONG>*</STRONG><EM>buf</EM><STRONG>)</STRONG>
<STRONG>int</STRONG> <STRONG>lstat(const</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG><EM>path</EM><STRONG>,</STRONG> <STRONG>struct</STRONG> <STRONG>stat</STRONG> <STRONG>*</STRONG><EM>buf</EM><STRONG>)</STRONG> <STRONG>(Minix</STRONG>-<STRONG>vmd)</STRONG>
<STRONG>int</STRONG> <STRONG>fstat(int</STRONG> <EM>fd</EM><STRONG>,</STRONG> <STRONG>struct</STRONG> <STRONG>stat</STRONG> <STRONG>*</STRONG><EM>buf</EM><STRONG>)</STRONG>
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<H2>DESCRIPTION</H2><PRE>
<STRONG>Stat</STRONG> obtains information about the file <EM>path</EM>. Read, write or execute
permission of the named file is not required, but all directories listed
in the path name leading to the file must be reachable.
<STRONG>Lstat</STRONG> is like <STRONG>stat</STRONG> except in the case where the named file is a symbolic
link, in which case <STRONG>lstat</STRONG> returns information about the link, while <STRONG>stat</STRONG>
returns information about the file the link references. (Minix-vmd)
<STRONG>Fstat</STRONG> obtains the same information about an open file referenced by the
argument descriptor, such as would be obtained by an <STRONG>open</STRONG> call. Pipe
descriptors look like named pipes with a link count of zero. The st_size
field of pipes or named pipes shows the amount of bytes currently
buffered in the pipe.
<EM>Buf</EM> is a pointer to a <STRONG>stat</STRONG> structure into which information is placed
concerning the file. The contents of the structure pointed to by <EM>buf</EM> is
as follows:
struct stat {
dev_t st_dev; /* device inode resides on */
ino_t st_ino; /* this inode's number */
mode_t st_mode; /* file mode, protection bits, etc. */
nlink_t st_nlink; /* number or hard links to the file */
uid_t st_uid; /* user-id of the file's owner */
gid_t st_gid; /* group-id of the file's owner */
dev_t st_rdev; /* the device type, for inode that is device */
off_t st_size; /* total size of file */
time_t st_atime; /* time of last access */
time_t st_mtime; /* time of last data modification */
time_t st_ctime; /* time of last file status change */
};
st_atime Time when file data was last read or modified. Changed by
the following system calls: <STRONG><A HREF="../man2/mknod.2.html">mknod(2)</A></STRONG>, <STRONG><A HREF="../man2/utime.2.html">utime(2)</A></STRONG>, <STRONG><A HREF="../man2/read.2.html">read(2)</A></STRONG>, and
<STRONG><A HREF="../man2/write.2.html">write(2)</A></STRONG>. For reasons of efficiency, st_atime is not set
when a directory is searched, although this would be more
logical.
st_mtime Time when data was last modified. It is not set by changes
of owner, group, link count, or mode. Changed by the
following system calls: <STRONG><A HREF="../man2/mknod.2.html">mknod(2)</A></STRONG>, <STRONG><A HREF="../man2/utime.2.html">utime(2)</A></STRONG>, <STRONG><A HREF="../man2/write.2.html">write(2)</A></STRONG>.
st_ctime Time when file status was last changed. It is set both both
by writing and changing the i-node. Changed by the following
system calls: <STRONG><A HREF="../man2/chmod.2.html">chmod(2)</A></STRONG> <STRONG><A HREF="../man2/chown.2.html">chown(2)</A></STRONG>, <STRONG><A HREF="../man2/link.2.html">link(2)</A></STRONG>, <STRONG><A HREF="../man2/mknod.2.html">mknod(2)</A></STRONG>,
<STRONG><A HREF="../man2/rename.2.html">rename(2)</A></STRONG>, <STRONG><A HREF="../man2/unlink.2.html">unlink(2)</A></STRONG>, <STRONG><A HREF="../man2/utime.2.html">utime(2)</A></STRONG>, <STRONG><A HREF="../man2/write.2.html">write(2)</A></STRONG>.
The file type information in <STRONG>st_mode</STRONG> has bits:
#define S_IFMT 0170000 /* type of file */
#define S_IFIFO 0010000 /* named pipe */
#define S_IFCHR 0020000 /* character special */
#define S_IFDIR 0040000 /* directory */
#define S_IFBLK 0060000 /* block special */
#define S_IFREG 0100000 /* regular */
#define S_IFLNK 0120000 /* symbolic link (Minix-vmd) */
The mode bits 0007777 encode set-uid/gid bits and permission bits (see
<STRONG><A HREF="../man2/chmod.2.html">chmod(2)</A></STRONG>).
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<H2>RETURN VALUE</H2><PRE>
Upon successful completion a value of 0 is returned. Otherwise, a value
of -1 is returned and <STRONG>errno</STRONG> is set to indicate the error.
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<H2>ERRORS</H2><PRE>
<STRONG>Stat</STRONG> and <STRONG>lstat</STRONG> will fail if one or more of the following are true:
[ENOTDIR] A component of the path prefix is not a directory.
[ENAMETOOLONG] The path name exceeds PATH_MAX characters.
[ENOENT] The named file does not exist.
[EACCES] Search permission is denied for a component of the path
prefix.
[ELOOP] Too many symbolic links were encountered in translating
the pathname. (Minix-vmd)
[EFAULT] <EM>Buf</EM> or <EM>name</EM> points to an invalid address.
[EIO] An I/O error occurred while reading from or writing to the
file system.
<STRONG>Fstat</STRONG> will fail if one or both of the following are true:
[EBADF] <EM>Fildes</EM> is not a valid open file descriptor.
[EFAULT] <EM>Buf</EM> points to an invalid address.
[EIO] An I/O error occurred while reading from or writing to the
file system.
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<H2>SEE ALSO</H2><PRE>
<STRONG><A HREF="../man2/chmod.2.html">chmod(2)</A></STRONG>, <STRONG><A HREF="../man2/chown.2.html">chown(2)</A></STRONG>, <STRONG><A HREF="../man2/utime.2.html">utime(2)</A></STRONG>.
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