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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.\" $FreeBSD$ 30.\" 31.Dd December 1, 2017 32.Dt STAT 2 33.Os 34.Sh NAME 35.Nm stat , 36.Nm lstat , 37.Nm fstat , 38.Nm fstatat 39.Nd get file status 40.Sh LIBRARY 41.Lb libc 42.Sh SYNOPSIS 43.In sys/stat.h 44.Ft int 45.Fn stat "const char * restrict path" "struct stat * restrict sb" 46.Ft int 47.Fn lstat "const char * restrict path" "struct stat * restrict sb" 48.Ft int 49.Fn fstat "int fd" "struct stat *sb" 50.Ft int 51.Fn fstatat "int fd" "const char *path" "struct stat *buf" "int flag" 52.Sh DESCRIPTION 53The 54.Fn stat 55system call obtains information about the file pointed to by 56.Fa path . 57Read, write or execute 58permission of the named file is not required, but all directories 59listed in the path name leading to the file must be searchable. 60.Pp 61The 62.Fn lstat 63system call is like 64.Fn stat 65except when the named file is a symbolic link, 66in which case 67.Fn lstat 68returns information about the link, 69while 70.Fn stat 71returns information about the file the link references. 72.Pp 73The 74.Fn fstat 75system call obtains the same information about an open file 76known by the file descriptor 77.Fa fd . 78.Pp 79The 80.Fn fstatat 81system call is equivalent to 82.Fn stat 83and 84.Fn lstat 85except when the 86.Fa path 87specifies a relative path. 88In this case the status is retrieved from a file relative to 89the directory associated with the file descriptor 90.Fa fd 91instead of the current working directory. 92.Pp 93The values for the 94.Fa flag 95are constructed by a bitwise-inclusive OR of flags from this list, 96defined in 97.In fcntl.h : 98.Bl -tag -width indent 99.It Dv AT_SYMLINK_NOFOLLOW 100If 101.Fa path 102names a symbolic link, the status of the symbolic link is returned. 103.El 104.Pp 105If 106.Fn fstatat 107is passed the special value 108.Dv AT_FDCWD 109in the 110.Fa fd 111parameter, the current working directory is used and the behavior is 112identical to a call to 113.Fn stat 114or 115.Fn lstat 116respectively, depending on whether or not the 117.Dv AT_SYMLINK_NOFOLLOW 118bit is set in 119.Fa flag . 120.Pp 121The 122.Fa sb 123argument is a pointer to a 124.Vt stat 125structure 126as defined by 127.In sys/stat.h 128and into which information is placed concerning the file. 129.Pp 130The fields of 131.Vt "struct stat" 132related to the file system are: 133.Bl -tag -width ".Va st_nlink" 134.It Va st_dev 135Numeric ID of the device containing the file. 136.It Va st_ino 137The file's inode number. 138.It Va st_nlink 139Number of hard links to the file. 140.It Va st_flags 141Flags enabled for the file. 142See 143.Xr chflags 2 144for the list of flags and their description. 145.El 146.Pp 147The 148.Va st_dev 149and 150.Va st_ino 151fields together identify the file uniquely within the system. 152.Pp 153The time-related fields of 154.Vt "struct stat" 155are: 156.Bl -tag -width ".Va st_birthtim" 157.It Va st_atim 158Time when file data was last accessed. 159Changed by the 160.Xr mknod 2 , 161.Xr utimes 2 , 162.Xr read 2 163and 164.Xr readv 2 165system calls. 166.It Va st_mtim 167Time when file data was last modified. 168Changed by the 169.Xr mkdir 2 , 170.Xr mkfifo 2 , 171.Xr mknod 2 , 172.Xr utimes 2 , 173.Xr write 2 174and 175.Xr writev 2 176system calls. 177.It Va st_ctim 178Time when file status was last changed (inode data modification). 179Changed by the 180.Xr chflags 2 , 181.Xr chmod 2 , 182.Xr chown 2 , 183.Xr creat 2 , 184.Xr link 2 , 185.Xr mkdir 2 , 186.Xr mkfifo 2 , 187.Xr mknod 2 , 188.Xr rename 2 , 189.Xr rmdir 2 , 190.Xr symlink 2 , 191.Xr truncate 2 , 192.Xr unlink 2 , 193.Xr utimes 2 , 194.Xr write 2 195and 196.Xr writev 2 197system calls. 198.It Va st_birthtim 199Time when the inode was created. 200.El 201.Pp 202These time-related macros are defined for compatibility: 203.Bd -literal 204#define st_atime st_atim.tv_sec 205#define st_mtime st_mtim.tv_sec 206#define st_ctime st_ctim.tv_sec 207#ifndef _POSIX_SOURCE 208#define st_birthtime st_birthtim.tv_sec 209#endif 210 211#ifndef _POSIX_SOURCE 212#define st_atimespec st_atim 213#define st_mtimespec st_mtim 214#define st_ctimespec st_ctim 215#define st_birthtimespec st_birthtim 216#endif 217.Ed 218.Pp 219Size-related fields of the 220.Vt "struct stat" 221are: 222.Bl -tag -width ".Va st_blksize" 223.It Va st_size 224File size in bytes. 225.It Va st_blksize 226Optimal I/O block size for the file. 227.It Va st_blocks 228Actual number of blocks allocated for the file in 512-byte units. 229As short symbolic links are stored in the inode, this number may 230be zero. 231.El 232.Pp 233The access-related fields of 234.Vt "struct stat" 235are: 236.Bl -tag -width ".Va st_mode" 237.It Va st_uid 238User ID of the file's owner. 239.It Va st_gid 240Group ID of the file. 241.It Va st_mode 242Status of the file (see below). 243.El 244.Pp 245The status information word 246.Fa st_mode 247has these bits: 248.Bd -literal 249#define S_IFMT 0170000 /* type of file mask */ 250#define S_IFIFO 0010000 /* named pipe (fifo) */ 251#define S_IFCHR 0020000 /* character special */ 252#define S_IFDIR 0040000 /* directory */ 253#define S_IFBLK 0060000 /* block special */ 254#define S_IFREG 0100000 /* regular */ 255#define S_IFLNK 0120000 /* symbolic link */ 256#define S_IFSOCK 0140000 /* socket */ 257#define S_IFWHT 0160000 /* whiteout */ 258#define S_ISUID 0004000 /* set user id on execution */ 259#define S_ISGID 0002000 /* set group id on execution */ 260#define S_ISVTX 0001000 /* save swapped text even after use */ 261#define S_IRWXU 0000700 /* RWX mask for owner */ 262#define S_IRUSR 0000400 /* read permission, owner */ 263#define S_IWUSR 0000200 /* write permission, owner */ 264#define S_IXUSR 0000100 /* execute/search permission, owner */ 265#define S_IRWXG 0000070 /* RWX mask for group */ 266#define S_IRGRP 0000040 /* read permission, group */ 267#define S_IWGRP 0000020 /* write permission, group */ 268#define S_IXGRP 0000010 /* execute/search permission, group */ 269#define S_IRWXO 0000007 /* RWX mask for other */ 270#define S_IROTH 0000004 /* read permission, other */ 271#define S_IWOTH 0000002 /* write permission, other */ 272#define S_IXOTH 0000001 /* execute/search permission, other */ 273.Ed 274.Pp 275For a list of access modes, see 276.In sys/stat.h , 277.Xr access 2 278and 279.Xr chmod 2 . 280These macros are available to test whether a 281.Va st_mode 282value passed in the 283.Fa m 284argument corresponds to a file of the specified type: 285.Bl -tag -width ".Fn S_ISFIFO m" 286.It Fn S_ISBLK m 287Test for a block special file. 288.It Fn S_ISCHR m 289Test for a character special file. 290.It Fn S_ISDIR m 291Test for a directory. 292.It Fn S_ISFIFO m 293Test for a pipe or FIFO special file. 294.It Fn S_ISLNK m 295Test for a symbolic link. 296.It Fn S_ISREG m 297Test for a regular file. 298.It Fn S_ISSOCK m 299Test for a socket. 300.It Fn S_ISWHT m 301Test for a whiteout. 302.El 303.Pp 304The macros evaluate to a non-zero value if the test is true 305or to the value 0 if the test is false. 306.Sh RETURN VALUES 307.Rv -std 308.Sh COMPATIBILITY 309Previous versions of the system used different types for the 310.Va st_dev , 311.Va st_uid , 312.Va st_gid , 313.Va st_rdev , 314.Va st_size , 315.Va st_blksize 316and 317.Va st_blocks 318fields. 319.Sh ERRORS 320The 321.Fn stat 322and 323.Fn lstat 324system calls will fail if: 325.Bl -tag -width Er 326.It Bq Er EACCES 327Search permission is denied for a component of the path prefix. 328.It Bq Er EFAULT 329The 330.Fa sb 331or 332.Fa path 333argument 334points to an invalid address. 335.It Bq Er EIO 336An I/O error occurred while reading from or writing to the file system. 337.It Bq Er ELOOP 338Too many symbolic links were encountered in translating the pathname. 339.It Bq Er ENAMETOOLONG 340A component of a pathname exceeded 255 characters, 341or an entire path name exceeded 1023 characters. 342.It Bq Er ENOENT 343The named file does not exist. 344.It Bq Er ENOTDIR 345A component of the path prefix is not a directory. 346.It Bq Er EOVERFLOW 347The file size in bytes cannot be 348represented correctly in the structure pointed to by 349.Fa sb . 350.El 351.Pp 352The 353.Fn fstat 354system call will fail if: 355.Bl -tag -width Er 356.It Bq Er EBADF 357The 358.Fa fd 359argument 360is not a valid open file descriptor. 361.It Bq Er EFAULT 362The 363.Fa sb 364argument 365points to an invalid address. 366.It Bq Er EIO 367An I/O error occurred while reading from or writing to the file system. 368.It Bq Er EOVERFLOW 369The file size in bytes cannot be 370represented correctly in the structure pointed to by 371.Fa sb . 372.El 373.Pp 374In addition to the errors returned by the 375.Fn lstat , 376the 377.Fn fstatat 378may fail if: 379.Bl -tag -width Er 380.It Bq Er EBADF 381The 382.Fa path 383argument does not specify an absolute path and the 384.Fa fd 385argument is neither 386.Dv AT_FDCWD 387nor a valid file descriptor open for searching. 388.It Bq Er EINVAL 389The value of the 390.Fa flag 391argument is not valid. 392.It Bq Er ENOTDIR 393The 394.Fa path 395argument is not an absolute path and 396.Fa fd 397is neither 398.Dv AT_FDCWD 399nor a file descriptor associated with a directory. 400.El 401.Sh SEE ALSO 402.Xr access 2 , 403.Xr chmod 2 , 404.Xr chown 2 , 405.Xr fhstat 2 , 406.Xr statfs 2 , 407.Xr utimes 2 , 408.Xr sticky 7 , 409.Xr symlink 7 410.Sh STANDARDS 411The 412.Fn stat 413and 414.Fn fstat 415system calls are expected to conform to 416.St -p1003.1-90 . 417The 418.Fn fstatat 419system call follows The Open Group Extended API Set 2 specification. 420.Sh HISTORY 421The 422.Fn stat 423and 424.Fn fstat 425system calls appeared in 426.At v1 . 427The 428.Fn lstat 429system call appeared in 430.Bx 4.2 . 431The 432.Fn fstatat 433system call appeared in 434.Fx 8.0 . 435.Sh BUGS 436Applying 437.Fn fstat 438to a socket 439returns a zeroed buffer, 440except for the blocksize field, 441and a unique device and inode number. 442