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STATVFS(3) FreeBSD Library Functions Manual STATVFS(3)
NAME
statvfs, fstatvfs - retrieve file system information
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <sys/statvfs.h>
int
statvfs(const char * restrict path, struct statvfs * restrict buf);
int
fstatvfs(int fd, struct statvfs *buf);
DESCRIPTION
The statvfs() and fstatvfs() functions fill the structure pointed to by
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 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 struct statfs.)
f_bsize The preferred length of I/O requests for files on this
file system. (Corresponds to the f_iosize member of
struct statfs.)
f_flag Flags describing mount options for this file system; see
below.
In addition, there are three members of type 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 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
otherwise the value -1 is returned and the global variable errno is set
to indicate the error.
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:
[EOVERFLOW] One or more of the file system statistics has a value
which cannot be represented by the data types used in
struct statvfs.
SEE ALSO
pathconf(2), statfs(2)
STANDARDS
The statvfs() and fstatvfs() functions conform to IEEE Std 1003.1-2001
("POSIX.1"). 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 FreeBSD 5.0.
AUTHORS
The statvfs() and fstatvfs() functions and this manual page were written
by Garrett Wollman <wollman@FreeBSD.org>.
FreeBSD 14.0-RELEASE-p11 July 13, 2002 FreeBSD 14.0-RELEASE-p11