statvfs(2)                                                       statvfs(2)

NAME
     statvfs, fstatvfs, statvfs64, fstatvfs64 - get file system information

SYNOPSIS
     #include <sys/types.h>
     #include <sys/statvfs.h>

     int statvfs(const char *path, struct statvfs *buf);

     int fstatvfs(int fildes, struct statvfs *buf);

     int statvfs64(const char *path, struct statvfs64 *buf);

     int fstatvfs64(int fildes, struct statvfs64 *buf);

DESCRIPTION
     statvfs() returns a "generic superblock" describing a file system; it
     can be used to acquire information about mounted file systems. buf is
     a pointer to a structure (described below) that is filled by the sys-
     tem call.

     path should name a file that resides on that file system. The file
     system type is known to the operating system. Read, write, or execute
     permission for the named file is not required, but all directories
     listed in the pathname leading to the file must be searchable.

     There is no functional difference between statvfs()/fstatvfs() and
     statvfs64()/fstatvfs64(), except for the interpretation of
     statvfs/statvfs64 [see statvfs(5)].

     The statvfs structure pointed to by buf includes the following
     members:

     ulongt    fbsize;             /* optimal I/O size for read and write */
     ulongt    ffrsize;            /* fundamental file system block size */
     fsblkcntt fblocks;            /* total # of blocks on file system
                                        in units of ffrsize */
     fsblkcntt fbfree;             /* total # of free blocks
                                        in units of ffrsize */
     fsblkcntt fbavail;            /* # of free blocks avail to non-superuser
                                        in units of ffrsize */
     fsfilcntt ffiles;             /* total # of file nodes (inodes) */
     fsfilcntt fffree;             /* total # of free file nodes */
     fsfilcntt ffavail;            /* # of inodes avail to non-superuser */
     ulongt    ffsid;              /* file system id (dev for now) */
     char       fbasetype[FSTYPSZ]; /* target fs type name, null-terminated */
     ulongt    fflag;              /* bit mask of flags */
     ulongt    fnamemax;           /* maximum filename length */
     char       ffstr[32];          /* file system specific string */
     ulongt    ffiller[16];        /* reserved for future expansion */





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statvfs(2)                                                       statvfs(2)

     fbasetype contains a null-terminated FSType name of the mounted tar-
     get (e.g. ufs mounted over nfs will contain ufs).

     The following flags can be returned in the fflag field:

     STRDONLY     0x01    /* read-only file system */
     STNOSUID     0x02    /* does not support setuid/setgid semantics */
     STNOTRUNC    0x04    /* does not truncate filenames longer than
                              NAMEMAX */

     fstatvfs() is similar to statvfs(), except that the file named by path
     in statvfs() is instead identified by an open file descriptor fildes
     obtained from a successful open(), creat(), dup(), fcntl(), or pipe()
     system call.

ERRORS
     The following error code descriptions are function-specific. You will
     find a general description in introprm2(2) or in errno(5).

     statvfs() and statvfs() fail if one or more of the following apply:

     EINTR         A signal was caught during execution of the function.

     EIO           An I/O error occurred while reading the file system.

     EOVERFLOW     One of the values to be returned cannot be represented
                   correctly in the structure pointed to by buf.

     statvfs() fails if one or more of the following apply:

     EACCES        Search permission is denied on a component of the path
                   prefix.

     EFAULT        path or buf points outside the process' allocated
                   address space.

     ELOOP         Too many symbolic links were encountered in translating
                   path.

     EMULTIHOP     Components of path require hopping to multiple remote
                   machines and the file system does not allow it.

     ENAMETOOLONG  The length of a path component exceeds NAMEMAX charac-
                   ters, or the length of path exceeds PATHMAX characters.

     ENOENT        Either a component of the path prefix or the file
                   referred to by path does not exist.

     ENOLINK       path points to a remote machine and the link to that
                   machine is no longer active.

     ENOTDIR       A component of the path prefix of path is not a directory.


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statvfs(2)                                                       statvfs(2)

     fstatvfs() fails if one or more of the following apply:

     EFAULT        buf points to an invalid address.

     EBADF         fildes is not an open file descriptor.

     statvfs() may fail if:

     ENAMETOOLONG  Pathname resolution of a symbolic link produced an
                   intermediate result whose length exceeds PATHMAX.

RESULT
     Upon successful completion a value of 0 is returned. Otherwise, a
     value of -1 is returned and errno is set to indicate the error.

NOTES
     fstatvfs() and statvfs() functions will fail if the total, or free, or
     available number of blocks or files cannot be represented correctly in
     the structure to be returned (fblocks, fbfree, fbavail, ffiles,
     fffree, ffavail).

SEE ALSO
     chmod(2), chown(2), creat(2), link(2), mknod(2), pipe(2), read(2),
     time(2), unlink(2), utime(2), write(2), lfs(5), statvfs(5), types(5).






























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