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Neither the name of the University nor the names of its contributors 13.\" may be used to endorse or promote products derived from this software 14.\" without specific prior written permission. 15.\" 16.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 17.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 20.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26.\" SUCH DAMAGE. 27.\" 28.\" @(#)stat.2 8.4 (Berkeley) 5/1/95 29.\" $FreeBSD: src/lib/libc/sys/stat.2,v 1.16.2.7 2001/12/14 18:34:01 ru Exp $ 30.\" $DragonFly: src/lib/libc/sys/stat.2,v 1.6 2008/09/28 16:33:35 swildner Exp $ 31.\" 32.Dd August 1, 2009 33.Dt STAT 2 34.Os 35.Sh NAME 36.Nm stat , 37.Nm lstat , 38.Nm fstat , 39.Nm fstatat 40.Nd get file status 41.Sh LIBRARY 42.Lb libc 43.Sh SYNOPSIS 44.In sys/types.h 45.In sys/stat.h 46.Ft int 47.Fn stat "const char *path" "struct stat *sb" 48.Ft int 49.Fn lstat "const char *path" "struct stat *sb" 50.Ft int 51.Fn fstat "int fd" "struct stat *sb" 52.Ft int 53.Fn fstatat "int fd" "const char *path" "struct stat *buf" "int flag" 54.Sh DESCRIPTION 55The 56.Fn stat 57system call obtains information about the file pointed to by 58.Fa path . 59Read, write or execute 60permission of the named file is not required, but all directories 61listed in the path name leading to the file must be searchable. 62.Pp 63.Fn Lstat 64is like 65.Fn stat 66except in the case where the named file is a symbolic link, 67in which case 68.Fn lstat 69returns information about the link, 70while 71.Fn stat 72returns information about the file the link references. 73.Pp 74The 75.Fn fstat 76system call obtains the same information about an open file 77known by the file descriptor 78.Fa fd . 79.Pp 80The 81.Fn fstatat 82system call is equivalent to 83.Fn stat 84and 85.Fn lstat 86except in the case where the 87.Fa path 88specifies a relative path. 89In this case the status is retrieved from a file relative to 90the directory associated with the file descriptor 91.Fa fd 92instead of the current working directory. 93.Pp 94The values for the 95.Fa flag 96are constructed by a bitwise-inclusive OR of flags from the following list, 97defined in 98.In fcntl.h : 99.Bl -tag -width indent 100.It Dv AT_SYMLINK_NOFOLLOW 101If 102.Fa path 103names a symbolic link, the status of the symbolic link is returned. 104.El 105.Pp 106If 107.Fn fstatat 108is passed the special value 109.Dv AT_FDCWD 110in the 111.Fa fd 112parameter, the current working directory is used and the behavior is 113identical to a call to 114.Fn stat 115or 116.Fn lstat 117respectively, depending on whether or not the 118.Dv AT_SYMLINK_NOFOLLOW 119bit is set in 120.Fa flag . 121.Pp 122The 123.Fa sb 124argument is a pointer to a 125.Vt stat 126structure 127as defined by 128.In sys/stat.h 129(shown below) 130and into which information is placed concerning the file. 131.Bd -literal 132struct stat { 133 dev_t st_dev; /* inode's device */ 134 ino_t st_ino; /* inode's number */ 135 mode_t st_mode; /* inode protection mode */ 136 nlink_t st_nlink; /* number of hard links */ 137 uid_t st_uid; /* user ID of the file's owner */ 138 gid_t st_gid; /* group ID of the file's group */ 139 dev_t st_rdev; /* device type */ 140#ifndef _POSIX_SOURCE 141 struct timespec st_atimespec; /* time of last access */ 142 struct timespec st_mtimespec; /* time of last data modification */ 143 struct timespec st_ctimespec; /* time of last file status change */ 144#else 145 time_t st_atime; /* time of last access */ 146 long st_atimensec; /* nsec of last access */ 147 time_t st_mtime; /* time of last data modification */ 148 long st_mtimensec; /* nsec of last data modification */ 149 time_t st_ctime; /* time of last file status change */ 150 long st_ctimensec; /* nsec of last file status change */ 151#endif 152 off_t st_size; /* file size, in bytes */ 153 int64_t st_blocks; /* blocks allocated for file */ 154 u_int32_t st_blksize; /* optimal blocksize for I/O */ 155 u_int32_t st_flags; /* user defined flags for file */ 156 u_int32_t st_gen; /* file generation number */ 157}; 158.Ed 159.Pp 160The time-related fields of 161.Vt struct stat 162are as follows: 163.Bl -tag -width ".Fa st_mtime" 164.It Fa st_atime 165Time when file data last accessed. 166Changed by the 167.Xr execve 2 , 168.Xr mknod 2 , 169.Xr mmap 2 , 170.Xr read 2 171and 172.Xr utimes 2 173system calls. 174.It Fa st_mtime 175Time when file data last modified. 176Changed by the 177.Xr mknod 2 , 178.Xr utimes 2 179and 180.Xr write 2 181system calls. 182.It Fa st_ctime 183Time when file status was last changed (inode data modification). 184Changed by the 185.Xr chmod 2 , 186.Xr chown 2 , 187.Xr link 2 , 188.Xr mknod 2 , 189.Xr rename 2 , 190.Xr unlink 2 , 191.Xr utimes 2 192and 193.Xr write 2 194system calls. 195.El 196.Pp 197If 198.Dv _POSIX_SOURCE 199is not defined, the time-related fields are defined as: 200.Bd -literal 201#ifndef _POSIX_SOURCE 202#define st_atime st_atimespec.tv_sec 203#define st_mtime st_mtimespec.tv_sec 204#define st_ctime st_ctimespec.tv_sec 205#endif 206.Ed 207.Pp 208The size-related fields of the 209.Vt struct stat 210are as follows: 211.Bl -tag -width ".Fa st_blksize" 212.It Fa st_blksize 213The optimal I/O block size for the file. 214.It Fa st_blocks 215The actual number of blocks allocated for the file in 512-byte units. 216As short symbolic links are stored in the inode, this number may 217be zero. 218.El 219.Pp 220The status information word 221.Fa st_mode 222has the following bits: 223.Bd -literal 224#define S_IFMT 0170000 /* type of file */ 225#define S_IFIFO 0010000 /* named pipe (fifo) */ 226#define S_IFCHR 0020000 /* character special */ 227#define S_IFDIR 0040000 /* directory */ 228#define S_IFBLK 0060000 /* block special */ 229#define S_IFREG 0100000 /* regular */ 230#define S_IFLNK 0120000 /* symbolic link */ 231#define S_IFSOCK 0140000 /* socket */ 232#define S_IFWHT 0160000 /* whiteout */ 233#define S_ISUID 0004000 /* set user id on execution */ 234#define S_ISGID 0002000 /* set group id on execution */ 235#define S_ISVTX 0001000 /* save swapped text even after use */ 236#define S_IRUSR 0000400 /* read permission, owner */ 237#define S_IWUSR 0000200 /* write permission, owner */ 238#define S_IXUSR 0000100 /* execute/search permission, owner */ 239.Ed 240.Pp 241For a list of access modes, see 242.In sys/stat.h , 243.Xr access 2 244and 245.Xr chmod 2 . 246.Sh RETURN VALUES 247.Rv -std 248.Sh COMPATIBILITY 249Previous versions of the system used different types for the 250.Fa st_dev , 251.Fa st_uid , 252.Fa st_gid , 253.Fa st_rdev , 254.Fa st_size , 255.Fa st_blksize 256and 257.Fa st_blocks 258fields. 259.Sh ERRORS 260.Fn Stat 261and 262.Fn lstat 263will fail if: 264.Bl -tag -width Er 265.It Bq Er EACCES 266Search permission is denied for a component of the path prefix. 267.It Bq Er EIO 268An I/O error occurred while reading from or writing to the file system. 269.It Bq Er ELOOP 270Too many symbolic links were encountered in translating the pathname. 271.It Bq Er ENAMETOOLONG 272A component of a pathname exceeded 255 characters, 273or an entire path name exceeded 1023 characters. 274.It Bq Er ENOENT 275The named file does not exist. 276.It Bq Er ENOTDIR 277A component of the path prefix is not a directory. 278.It Bq Er EFAULT 279.Fa sb 280or 281.Em name 282points to an invalid address. 283.El 284.Pp 285.Fn Fstat 286will fail if: 287.Bl -tag -width Er 288.It Bq Er EBADF 289.Fa fd 290is not a valid open file descriptor. 291.It Bq Er EFAULT 292.Fa sb 293points to an invalid address. 294.It Bq Er EIO 295An I/O error occurred while reading from or writing to the file system. 296.El 297.Sh SEE ALSO 298.Xr access 2 , 299.Xr chmod 2 , 300.Xr chown 2 , 301.Xr statfs 2 , 302.Xr statvfs 2 , 303.Xr utimes 2 , 304.Xr symlink 7 305.Sh STANDARDS 306The 307.Fn stat 308and 309.Fn fstat 310system calls are expected to conform to 311.St -p1003.1-90 . 312.Sh HISTORY 313A 314.Fn stat 315and a 316.Fn fstat 317system call appeared in 318.At v7 . 319A 320.Fn lstat 321system call appeared in 322.Bx 4.2 . 323The 324.Fn fstatat 325system call appeared in 326.Dx 2.3 . 327.Sh BUGS 328Applying 329.Fn fstat 330to a socket (and thus to a pipe) 331returns a zeroed buffer, 332except for the blocksize field, 333and a unique device and inode number. 334