OpenBSD-4.6/lib/libc/gen/statvfs.3

.\"	$OpenBSD: statvfs.3,v 1.5 2008/03/26 09:37:59 jmc Exp $
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.\"	@(#)statfs.2	8.3 (Berkeley) 2/11/94
.\"
.Dd $Mdocdate: March 26 2008 $
.Dt STATVFS 3
.Os
.Sh NAME
.Nm statvfs ,
.Nm fstatvfs
.Nd get file system statistics
.Sh SYNOPSIS
.Fd #include <sys/statvfs.h>
.Ft int
.Fn statvfs "const char *path" "struct statvfs *buf"
.Ft int
.Fn fstatvfs "int fd" "struct statvfs *buf"
.Sh DESCRIPTION
.Fn statvfs
returns information about a mounted file system.
.Fa path
is the path name of any file within the mounted file system.
.Fa buf
is a pointer to a
.Nm statvfs
structure defined as follows:
.Bd -literal
struct statvfs {
        unsigned long f_bsize;    /* file system block size */
        unsigned long f_frsize;   /* fundamental file system block size */
        fsblkcnt_t    f_blocks;   /* number of blocks (unit f_frsize) */
        fsblkcnt_t    f_bfree;    /* free blocks in file system */
        fsblkcnt_t    f_bavail;   /* free blocks for non-root */
        fsfilcnt_t    f_files;    /* total file inodes */
        fsfilcnt_t    f_ffree;    /* free file inodes */
        fsfilcnt_t    f_favail;   /* free file inodes for to non-root */
        unsigned long f_fsid;     /* file system id */
        unsigned long f_flag;     /* bit mask of f_flag values */
        unsigned long f_namemax;  /* maximum filename length */
};

#define ST_RDONLY     0x0001UL    /* read-only filesystem */
#define	ST_NOSUID     0x0002UL    /* nosuid flag set */
.Ed
.Pp
The fields of type
.Va fsblkcnt_t
are reported in units of
.Va f_frsize .
.Pp
.Fn fstatvfs
returns the same information about an open file referenced by descriptor
.Fa fd .
.Sh RETURN VALUES
Upon successful completion, a value of 0 is returned.
Otherwise, \-1 is returned and the global variable
.Va errno
is set to indicate the error.
.Sh ERRORS
.Fn statvfs
fails if one or more of the following are true:
.Bl -tag -width Er
.It Bq Er ENOTDIR
A component of the path prefix of
.Fa path
is not a directory.
.It Bq Er ENAMETOOLONG
The length of a component of
.Fa path
exceeds
.Dv {NAME_MAX}
characters, or the length of
.Fa path
exceeds
.Dv {PATH_MAX}
characters.
.It Bq Er ENOENT
The file referred to by
.Fa path
does not exist.
.It Bq Er EACCES
Search permission is denied for a component of the path prefix of
.Fa path .
.It Bq Er ELOOP
Too many symbolic links were encountered in translating
.Fa path .
.It Bq Er EFAULT
.Fa buf
or
.Fa path
points to an invalid address.
.It Bq Er EIO
An
.Tn I/O
error occurred while reading from or writing to the file system.
.El
.Pp
.Fn fstatvfs
fails if one or more of the following are true:
.Bl -tag -width Er
.It Bq Er EBADF
.Fa fd
is not a valid open file descriptor.
.It Bq Er EFAULT
.Fa buf
points to an invalid address.
.It Bq Er EIO
An
.Tn I/O
error occurred while reading from or writing to the file system.
.El
.Sh SEE ALSO
.Xr df 1 ,
.Xr mount 2 ,
.Xr stat 2 ,
.Xr statfs 2
.Sh STANDARDS
The
.Fn statvfs
and
.Fn fstatvfs
functions conform to
.St -p1003.1-2001 .
.Sh HISTORY
The
.Fn statvfs
and
.Fn fstatvfs
functions first appeared in
.Ox 4.4 .