statvfs(2)                                                   statvfs(2)

  statvfs()

  NAME

    fstatvfs(), statvfs(), wcs_statvfs() - get information about file system

  SYNOPSIS

    #include 

    int fstatvfs(int fildes, struct statvfs *buf)
    int statvfs(const char *path, struct statvfs *buf)
    int wcs_statvfs(const wchar_t *path, struct wstatvfs *buf)

  DESCRIPTION

    The statvfs(2) and wcs_statvfs(2) functions are identical, except that
    wcs_statvfs(2) accepts wide characters in the path argument and in the
    structure referenced by the buf argument.

    These three functions return information about the file system by filling
    the statvfs structure referenced by buf. The fstatvfs(2) function returns
    information about the file referenced by the file descriptor fildes; the
    statvfs(2) or wcs_statvfs(2) function returns information about the file
    named by path.

    The calling process does not need read, write, or execute permission on
    the file. For statvfs(2) or wcs_statvfs(2), the calling process must be
    able to search all of the directories in the file's absolute path name, or
    an [EACCES] error will result.

    The statvfs structure contains the following members:
    Type              Member

    unsigned long     f_bsize

    unsigned long     f_frsize

    unsigned long     f_blocks

    unsigned long     f_bfree

    unsigned long     f_bavail

    unsigned long     f_files

    unsigned long     f_ffree

    unsigned long     f_favail

    unsigned long     f_fsid

    unsigned long     f_flag

    unsigned long     f_namemax

    unsigned long     f_type

    unsigned long     f_iosize

    char              f_mntonname[MNAMELEN+1]

    char              f_mntfromname[MNAMELEN+1]

    The wstatvfs structure is identical to the stavfs structure except for the
    data type of the following two members:
    Type        Member

    wchar_t     f_mntonname[MNAMELEN+1]

    wchar_t     f_mntfromname[MNAMELEN+1]

    The members represent:

    f_bsize
        The block size on the file system.

    f_frsize
        Fundamental block size on the file system.

    f_blocks
        Total number of blocks on the file system in units of f_frsize.

    f_bfree
        Total number of free blocks.

    f_bavail
        Total number of free blocks available to a non-privileged process.

    f_files
        Total number of file serial numbers on the file system.

    f_ffree
        Total number of free file serial numbers on the file system.

    f_favail
        Total number of file serial numbers available to a non-privileged
        process.

    f_fsid
        ID of the file system.

    f_flag
        A bit mask of values describing the file system; defined values are:

        ST_RDONLY
            A read-only file system.

        ST_NOSUID
            The file system does not support setuid/setgid semantics.

    f_namemax
        The maximum length of a file name on the file system.

    f_type
        The type of the file system, which is one of the following:

        ST_FSTYPE_CDFS
            ISO 9660 CD-ROM drive.

        ST_FSTYPE_CDROM
            ISO 9660 CD-ROM drive.

        ST_FSTYPE_HPFS
            IBM OS/2 High Performance File System.

        ST_FSTYPE_ISO9660
            ISO 9660 CD-ROM drive.

        ST_FSTYPE_NTFS
            NTFS file system.

        ST_FSTYPE_OFS
            OFS (Microsoft Windows Object File System).

        ST_FSTYPE_SAMBA
            Samba SMB file system.

        ST_FSTYPE_NFS
            Network file system (NFS)

        ST_FSTYPE_UNKNOWN
            Unknown file system type.

    f_iosize
        Optimal transfer block size.

    f_mntonname
        The mountpoint for the file system. This is normally a path name
        corresponding to a drive letter, such as /dev/fs/C or /dev/fs/F.

    f_mntfromname
        The mounted file system.

  RETURN VALUE

    On success, each function returns 0. Otherwise, it returns -1 and sets
    errno to indicate the error.

  ERRORS

    All three functions will fail if:

    [EINVAL]
        The device holding the file system does not support the operation.

    [EIO]
        An input/output (I/O) error occurred while reading from or writing to
        the file system.

    [EINTR]
        A signal was caught while the function was executing.

    In addition, fstatvfs(2) will fail if:

    [EBADF]
        The descriptor fildes is invalid.

    The statvfs(2) or wcs_statvfs(2) function will fail if:

    [EACCES]
        The calling process did not have search permission on a directory in
        the file's path name.

    [ENAMETOOLONG]
        A component of the file's path name exceeded {NAME_MAX} characters, or
        the entire path name exceeded {PATH_MAX} characters.

    [ENOENT]
        The file does not exist.

    [ENOTDIR]
        Some component of the path prefix is not a directory.

  SEE ALSO

    stat(2)

  USAGE NOTES

    All of these functions are thread safe.

    None of these functions are async-signal safe.