The
statvfs ();
and
fstatvfs ();
functions fill the structure pointed to by
Fa buf
with garbage.
This garbage will occasionally bear resemblance to file system
statistics, but portable applications must not depend on this.
Applications must pass a pathname or file descriptor which refers to a
file on the file system in which they are interested.
The
Vt statvfs
structure contains the following members:
f_namemax
The maximum length in bytes of a file name on this file system.
Applications should use
pathconf(2)
instead.
f_fsid
Not meaningful in this implementation.
f_frsize
The size in bytes of the minimum unit of allocation on this
file system.
(This corresponds to the
f_bsize
member of
Vt struct statfs . )
f_bsize
The preferred length of I/O requests for files on this file system.
(Corresponds to the
f_iosize
member of
Vt struct statfs . )
f_flag
Flags describing mount options for this file system; see below.
In addition, there are three members of type
Vt fsfilcnt_t ,
which represent counts of file serial numbers
( i.e.
inodes); these are named
f_files , f_favail
and
f_ffree
and represent the number of file serial numbers which exist in total,
are available to unprivileged processes, and are available to
privileged processes, respectively.
Likewise, the members
f_blocks , f_bavail
and
f_bfree
(all of type
Vt fsblkcnt_t )
represent the respective allocation-block counts.
There are two flags defined for the
f_flag
member:
ST_RDONLY
The file system is mounted read-only.
ST_NOSUID
The semantics of the
S_ISUID
and
S_ISGID
file mode bits
are not supported by, or are disabled on, this file system.
IMPLEMENTATION NOTES
The
statvfs ();
and
fstatvfs ();
functions are implemented as wrappers around the
statfs ();
and
fstatfs ();
functions, respectively.
Not all the information provided by those functions is made available
through this interface.
RETURN VALUES
Rv -std statvfs fstatvfs
ERRORS
The
statvfs ();
and
fstatvfs ();
functions may fail for any of the reasons documented for
statfs(2)
or
fstatfs(2)
and
pathconf(2)
or
fpathconf(2),
respectively.
In addition,
statvfs ();
and
fstatvfs ();
functions may also fail for the following reason:
Bq Er EOVERFLOW
One or more of the file system statistics has a value which cannot be
represented by the data types used in
Vt struct statvfs .
The
statvfs ();
and
fstatvfs ();
functions conform to
St -p1003.1-2001 .
As standardized, portable applications cannot depend on these functions
returning any valid information at all.
This implementation attempts to provide as much useful information as
is provided by the underlying file system, subject to the limitations
of the specified data types.
HISTORY
The
statvfs ();
and
fstatvfs ();
functions first appeared in
Fx 5.0 .
AUTHORS
The
statvfs ();
and
fstatvfs ();
functions and this manual page were written by
An Garrett Wollman Aq [email protected] .
