fstat#
Synopsis#
#include <sys/stat.h>
int fstat(int fildes, struct stat *buf);
Status#
Implemented
Conformance#
IEEE Std 1003.1-2017
Description#
The fstat()
function shall obtain information about an open file associated with the file descriptor fildes, and
shall write it to the area pointed to by buf.
If fildes references a shared memory object, the implementation shall update in the stat structure pointed to by the
buf argument the st_uid
, st_gid
, st_size
, and st_mode
fields, and only the S_IRUSR
, S_IWUSR
, S_IRGRP
,
S_IWGRP
, S_IROTH
, and S_IWOTH
file permission bits need be valid. The implementation may update other fields
and flags.
If fildes references a typed memory object, the implementation shall update in the stat structure pointed to by the
buf argument the st_uid
, st_gid
, st_size
, and st_mode
fields, and only the S_IRUSR
, S_IWUSR
, S_IRGRP
,
S_IWGRP
, S_IROTH
, and S_IWOTH
file permission bits need be valid. The implementation may update other fields and
flags.
The buf argument is a pointer to a stat structure, as defined in <sys/stat.h>
, into which information is placed
concerning the file.
For all other file types defined in this volume of POSIX.1-2017
, the structure members st_mode
, st_ino
, st_dev
,
st_uid
, st_gid
, st_atim
, st_ctim
, and st_mtim
shall have meaningful values and the value of the st_nlink
member shall be set to the number of links to the file.
An implementation that provides additional or alternative file access control mechanisms may, under
implementation-defined conditions, cause fstat()
to fail.
The fstat()
function shall update any time-related fields, before writing into the stat structure.
Return value#
Upon successful completion, 0
shall be returned. Otherwise, -1
shall be returned and errno
set to indicate the
error.
Errors#
The fstat()
function shall fail if:
[EBADF]
- The fildes argument is not a valid file descriptor.[EIO]
- AnI/O
error occurred while reading from the file system.[EOVERFLOW]
- The file size in bytes or the number of blocks allocated to the file or the file serial number cannot be represented correctly in the structure pointed to by buf.
The fstat()
function may fail if:
[EOVERFLOW]
- One of the values is too large to store into the structure pointed to by the buf argument.
Tests#
Tested
Known bugs#
None