1.\" Copyright (c) 1980, 1991 Regents of the University of California. 2.\" All rights reserved. 3.\" 4.\" %sccs.include.redist.man% 5.\" 6.\" @(#)stat.2 6.11 (Berkeley) 05/31/93 7.\" 8.Dd 9.Dt STAT 2 10.Os BSD 4 11.Sh NAME 12.Nm stat , 13.Nm lstat , 14.Nm fstat 15.Nd get file status 16.Sh SYNOPSIS 17.Fd #include <sys/types.h> 18.Fd #include <sys/stat.h> 19.Ft int 20.Fn stat "const char *path" "struct stat *buf" 21.Ft int 22.Fn lstat "const char *path" "struct stat *buf" 23.Ft int 24.Fn fstat "int fd" "struct stat *buf" 25.Sh DESCRIPTION 26The 27.Fn stat 28function obtains information about the file pointed to by 29.Fa path . 30Read, write or execute 31permission of the named file is not required, but all directories 32listed in the path name leading to the file must be seachable. 33.Pp 34.Fn Lstat 35is like 36.Fn stat 37except in the case where the named file is a symbolic link, 38in which case 39.Fn lstat 40returns information about the link, 41while 42.Fn stat 43returns information about the file the link references. 44Unlike other filesystem objects, 45symbolic links do not have an owner, group, access mode, times, etc. 46Instead, these attributes are taken from the directory that 47contains the link. 48The only attributes returned from an 49.Fn lstat 50that refer to the symbolic link itself are the file type (S_IFLNK), 51size, blocks, and link count (always 1). 52.Pp 53The 54.Fn fstat 55obtains the same information about an open file 56known by the file descriptor 57.Fa fd , 58such as would 59be obtained by an 60.Xr open 61call. 62.Pp 63.Fa Buf 64is a pointer to a 65.Fn stat 66structure 67as defined by 68.Aq Pa sys/stat.h 69(shown below) 70and into which information is placed concerning the file. 71.Bd -literal 72struct stat { 73 dev_t st_dev; /* device inode resides on */ 74 ino_t st_ino; /* inode's number */ 75 mode_t st_mode; /* inode protection mode */ 76 nlink_t st_nlink; /* number or hard links to the file */ 77 uid_t st_uid; /* user-id of owner */ 78 gid_t st_gid; /* group-id of owner */ 79 dev_t st_rdev; /* device type, for special file inode */ 80 off_t st_size; /* file size, in bytes */ 81 time_t st_atime; /* time of last access */ 82 long st_spare1; 83 time_t st_mtime; /* time of last data modification */ 84 long st_spare2; 85 time_t st_ctime; /* time of last file status change */ 86 long st_spare3; 87 long st_blksize;/* optimal file sys I/O ops blocksize */ 88 long st_blocks; /* blocks allocated for file */ 89 u_long st_flags; /* user defined flags for file */ 90 u_long st_gen; /* file generation number */ 91}; 92.Ed 93.Pp 94The time-related fields of 95.Fa struct stat 96are as follows: 97.Bl -tag -width st_blocks 98.It st_atime 99Time when file data last accessed. Changed by the following system 100calls: 101.Xr mknod 2 , 102.Xr utimes 2 , 103and 104.Xr read 2 . 105.It st_mtime 106Time when file data last modified. 107Changed by the following system calls: 108.Xr mknod 2 , 109.Xr utimes 2 , 110.Xr write 2 . 111.It st_ctime 112Time when file status was last changed (inode data modification). 113Changed by the following system calls: 114.Xr chmod 2 115.Xr chown 2 , 116.Xr link 2 , 117.Xr mknod 2 , 118.Xr rename 2 , 119.Xr unlink 2 , 120.Xr utimes 2 , 121.Xr write 2 . 122.It st_blocks 123The actual number of blocks allocated for the file in 512-byte units. 124.El 125.Pp 126The status information word 127.Fa st_mode 128has bits: 129.Bd -literal 130#define S_IFMT 0170000 /* type of file */ 131#define S_IFIFO 0010000 /* named pipe (fifo) */ 132#define S_IFCHR 0020000 /* character special */ 133#define S_IFDIR 0040000 /* directory */ 134#define S_IFBLK 0060000 /* block special */ 135#define S_IFREG 0100000 /* regular */ 136#define S_IFLNK 0120000 /* symbolic link */ 137#define S_IFSOCK 0140000 /* socket */ 138#define S_ISUID 0004000 /* set user id on execution */ 139#define S_ISGID 0002000 /* set group id on execution */ 140#define S_ISVTX 0001000 /* save swapped text even after use */ 141#define S_IRUSR 0000400 /* read permission, owner */ 142#define S_IWUSR 0000200 /* write permission, owner */ 143#define S_IXUSR 0000100 /* execute/search permission, owner */ 144.Ed 145.Pp 146For a list of access modes, see 147.Aq Pa sys/stat.h , 148.Xr access 2 149and 150.Xr chmod 2 . 151.Sh RETURN VALUES 152Upon successful completion a value of 0 is returned. 153Otherwise, a value of -1 is returned and 154.Va errno 155is set to indicate the error. 156.Sh ERRORS 157.Fn Stat 158and 159.Fn lstat 160will fail if: 161.Bl -tag -width ENAMETOOLONGAA 162.It Bq Er ENOTDIR 163A component of the path prefix is not a directory. 164.It Bq Er EINVAL 165The pathname contains a character with the high-order bit set. 166.It Bq Er ENAMETOOLONG 167A component of a pathname exceeded 255 characters, 168or an entire path name exceeded 1023 characters. 169.It Bq Er ENOENT 170The named file does not exist. 171.It Bq Er EACCES 172Search permission is denied for a component of the path prefix. 173.It Bq Er ELOOP 174Too many symbolic links were encountered in translating the pathname. 175.It Bq Er EFAULT 176.Fa Buf 177or 178.Em name 179points to an invalid address. 180.It Bq Er EIO 181An I/O error occurred while reading from or writing to the file system. 182.El 183.Pp 184.Bl -tag -width [EFAULT] 185.Fn Fstat 186will fail if: 187.It Bq Er EBADF 188.Fa fd 189is not a valid open file descriptor. 190.It Bq Er EFAULT 191.Fa Buf 192points to an invalid address. 193.It Bq Er EIO 194An I/O error occurred while reading from or writing to the file system. 195.El 196.Sh CAVEAT 197The fields in the stat structure currently marked 198.Fa st_spare1 , 199.Fa st_spare2 , 200and 201.Fa st_spare3 202are present in preparation for inode time stamps expanding 203to 64 bits. This, however, can break certain programs that 204depend on the time stamps being contiguous (in calls to 205.Xr utimes 2 ) . 206.Sh SEE ALSO 207.Xr chmod 2 , 208.Xr chown 2 , 209.Xr utimes 2 210.Xr symlink 7 211.Sh BUGS 212Applying 213.Xr fstat 214to a socket (and thus to a pipe) 215returns a zero'd buffer, 216except for the blocksize field, 217and a unique device and inode number. 218.Sh STANDARDS 219The 220.Fn stat 221and 222.Fn fstat 223function calls are expected to 224conform to IEEE Std 1003.1-1988 225.Pq Dq Tn POSIX . 226.Sh HISTORY 227A 228.Nm lstat 229function call appeared in 230.Bx 4.2 . 231