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1 | .\" Copyright (c) 1980, 1991 Regents of the University of California. |
2 | .\" All rights reserved. | |
3 | .\" | |
4 | .\" Redistribution and use in source and binary forms, with or without | |
5 | .\" modification, are permitted provided that the following conditions | |
6 | .\" are met: | |
7 | .\" 1. Redistributions of source code must retain the above copyright | |
8 | .\" notice, this list of conditions and the following disclaimer. | |
9 | .\" 2. Redistributions in binary form must reproduce the above copyright | |
10 | .\" notice, this list of conditions and the following disclaimer in the | |
11 | .\" documentation and/or other materials provided with the distribution. | |
12 | .\" 3. All advertising materials mentioning features or use of this software | |
13 | .\" must display the following acknowledgement: | |
14 | .\" This product includes software developed by the University of | |
15 | .\" California, Berkeley and its contributors. | |
16 | .\" 4. Neither the name of the University nor the names of its contributors | |
17 | .\" may be used to endorse or promote products derived from this software | |
18 | .\" without specific prior written permission. | |
19 | .\" | |
20 | .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND | |
21 | .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | |
22 | .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE | |
23 | .\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE | |
24 | .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL | |
25 | .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS | |
26 | .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) | |
27 | .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT | |
28 | .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY | |
29 | .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF | |
30 | .\" SUCH DAMAGE. | |
31 | .\" | |
32 | .\" @(#)stat.2 6.9 (Berkeley) 3/10/91 | |
33 | .\" | |
34 | .Dd March 10, 1991 | |
35 | .Dt STAT 2 | |
36 | .Os BSD 4 | |
37 | .Sh NAME | |
38 | .Nm stat , | |
39 | .Nm lstat , | |
40 | .Nm fstat | |
41 | .Nd get file status | |
42 | .Sh SYNOPSIS | |
43 | .Fd #include <sys/types.h> | |
44 | .Fd #include <sys/stat.h> | |
45 | .Ft int | |
46 | .Fn stat "const char *path" "struct stat *buf" | |
47 | .Ft int | |
48 | .Fn lstat "const char *path" "struct stat *buf" | |
49 | .Ft int | |
50 | .Fn fstat "int fd" "struct stat *buf" | |
51 | .Sh DESCRIPTION | |
52 | The | |
53 | .Fn stat | |
54 | function obtains information about the file pointed to by | |
55 | .Fa path . | |
56 | Read, write or execute | |
57 | permission of the named file is not required, but all directories | |
58 | listed in the path name leading to the file must be seachable. | |
59 | .Pp | |
60 | .Fn Lstat | |
61 | is like | |
62 | .Fn stat | |
63 | except in the case where the named file is a symbolic link, | |
64 | in which case | |
65 | .Fn lstat | |
66 | returns information about the link, | |
67 | while | |
68 | .Fn stat | |
69 | returns information about the file the link references. | |
70 | .Pp | |
71 | The | |
72 | .Fn fstat | |
73 | obtains the same information about an open file | |
74 | known by the file descriptor | |
75 | .Fa fd , | |
76 | such as would | |
77 | be obtained by an | |
78 | .Xr open | |
79 | call. | |
80 | .Pp | |
81 | .Fa Buf | |
82 | is a pointer to a | |
83 | .Fn stat | |
84 | structure | |
85 | as defined by | |
86 | .Aq Pa sys/stat.h | |
87 | (shown below) | |
88 | and into which information is placed concerning the file. | |
89 | .Bd -literal | |
90 | struct stat { | |
91 | dev_t st_dev; /* device inode resides on */ | |
92 | ino_t st_ino; /* inode's number */ | |
93 | mode_t st_mode; /* inode protection mode */ | |
94 | nlink_t st_nlink; /* number or hard links to the file */ | |
95 | uid_t st_uid; /* user-id of owner */ | |
96 | gid_t st_gid; /* group-id of owner */ | |
97 | dev_t st_rdev; /* device type, for special file inode */ | |
98 | off_t st_size; /* file size, in bytes */ | |
99 | time_t st_atime; /* time of last access */ | |
100 | long st_spare1; | |
101 | time_t st_mtime; /* time of last data modification */ | |
102 | long st_spare2; | |
103 | time_t st_ctime; /* time of last file status change */ | |
104 | long st_spare3; | |
105 | long st_blksize;/* optimal file sys I/O ops blocksize */ | |
106 | long st_blocks; /* blocks allocated for file */ | |
107 | u_long st_flags; /* user defined flags for file */ | |
108 | u_long st_gen; /* file generation number */ | |
109 | }; | |
110 | .Ed | |
111 | .Pp | |
112 | The time-related fields of | |
113 | .Fa struct stat | |
114 | are as follows: | |
115 | .Bl -tag -width st_blocks | |
116 | .It st_atime | |
117 | Time when file data last accessed. Changed by the following system | |
118 | calls: | |
119 | .Xr mknod 2 , | |
120 | .Xr utimes 2 , | |
121 | and | |
122 | .Xr read 2 . | |
123 | .It st_mtime | |
124 | Time when file data last modified. | |
125 | Changed by the following system calls: | |
126 | .Xr mknod 2 , | |
127 | .Xr utimes 2 , | |
128 | .Xr write 2 . | |
129 | .It st_ctime | |
130 | Time when file status was last changed (inode data modification). | |
131 | Changed by the following system calls: | |
132 | .Xr chmod 2 | |
133 | .Xr chown 2 , | |
134 | .Xr link 2 , | |
135 | .Xr mknod 2 , | |
136 | .Xr rename 2 , | |
137 | .Xr unlink 2 , | |
138 | .Xr utimes 2 , | |
139 | .Xr write 2 . | |
140 | .It st_blocks | |
141 | The actual number of blocks allocated for the file in 512-byte units. | |
142 | .El | |
143 | .Pp | |
144 | The status information word | |
145 | .Fa st_mode | |
146 | has bits: | |
147 | .Bd -literal | |
148 | #define S_IFMT 0170000 /* type of file */ | |
149 | #define S_IFIFO 0010000 /* named pipe (fifo) */ | |
150 | #define S_IFCHR 0020000 /* character special */ | |
151 | #define S_IFDIR 0040000 /* directory */ | |
152 | #define S_IFBLK 0060000 /* block special */ | |
153 | #define S_IFREG 0100000 /* regular */ | |
154 | #define S_IFLNK 0120000 /* symbolic link */ | |
155 | #define S_IFSOCK 0140000 /* socket */ | |
156 | #define S_ISUID 0004000 /* set user id on execution */ | |
157 | #define S_ISGID 0002000 /* set group id on execution */ | |
158 | #define S_ISVTX 0001000 /* save swapped text even after use */ | |
159 | #define S_IRUSR 0000400 /* read permission, owner */ | |
160 | #define S_IWUSR 0000200 /* write permission, owner */ | |
161 | #define S_IXUSR 0000100 /* execute/search permission, owner */ | |
162 | .Ed | |
163 | .Pp | |
164 | For a list of access modes, see | |
165 | .Aq Pa sys/stat.h , | |
166 | .Xr access 2 | |
167 | and | |
168 | .Xr chmod 2 . | |
169 | .Sh RETURN VALUES | |
170 | Upon successful completion a value of 0 is returned. | |
171 | Otherwise, a value of -1 is returned and | |
172 | .Va errno | |
173 | is set to indicate the error. | |
174 | .Sh ERRORS | |
175 | .Fn Stat | |
176 | and | |
177 | .Fn lstat | |
178 | will fail if: | |
179 | .Bl -tag -width ENAMETOOLONGAA | |
180 | .It Bq Er ENOTDIR | |
181 | A component of the path prefix is not a directory. | |
182 | .It Bq Er EINVAL | |
183 | The pathname contains a character with the high-order bit set. | |
184 | .It Bq Er ENAMETOOLONG | |
185 | A component of a pathname exceeded 255 characters, | |
186 | or an entire path name exceeded 1023 characters. | |
187 | .It Bq Er ENOENT | |
188 | The named file does not exist. | |
189 | .It Bq Er EACCES | |
190 | Search permission is denied for a component of the path prefix. | |
191 | .It Bq Er ELOOP | |
192 | Too many symbolic links were encountered in translating the pathname. | |
193 | .It Bq Er EFAULT | |
194 | .Fa Buf | |
195 | or | |
196 | .Em name | |
197 | points to an invalid address. | |
198 | .It Bq Er EIO | |
199 | An I/O error occurred while reading from or writing to the file system. | |
200 | .El | |
201 | .Pp | |
202 | .Bl -tag -width [EFAULT] | |
203 | .Fn Fstat | |
204 | will fail if: | |
205 | .It Bq Er EBADF | |
206 | .Fa fd | |
207 | is not a valid open file descriptor. | |
208 | .It Bq Er EFAULT | |
209 | .Fa Buf | |
210 | points to an invalid address. | |
211 | .It Bq Er EIO | |
212 | An I/O error occurred while reading from or writing to the file system. | |
213 | .El | |
214 | .Sh CAVEAT | |
215 | The fields in the stat structure currently marked | |
216 | .Fa st_spare1 , | |
217 | .Fa st_spare2 , | |
218 | and | |
219 | .Fa st_spare3 | |
220 | are present in preparation for inode time stamps expanding | |
221 | to 64 bits. This, however, can break certain programs that | |
222 | depend on the time stamps being contiguous (in calls to | |
223 | .Xr utimes 2 ) . | |
224 | .Sh SEE ALSO | |
225 | .Xr chmod 2 , | |
226 | .Xr chown 2 , | |
227 | .Xr utimes 2 | |
228 | .Sh BUGS | |
229 | Applying | |
230 | .Xr fstat | |
231 | to a socket (and thus to a pipe) | |
232 | returns a zero'd buffer, | |
233 | except for the blocksize field, | |
234 | and a unique device and inode number. | |
235 | .Sh STANDARDS | |
236 | The | |
237 | .Fn stat | |
238 | and | |
239 | .Fn fstat | |
240 | function calls are expected to | |
241 | conform to IEEE Std 1003.1-1988 | |
242 | .Pq Dq Tn POSIX . | |
243 | .Sh HISTORY | |
244 | A | |
245 | .Nm lstat | |
246 | function call appeared in | |
247 | .Bx 4.2 . |