usr/src/usr.bin/du/du.1

.\" Copyright (c) 1990 The Regents of the University of California.
.\" All rights reserved.
.\"
.\" %sccs.include.redist.roff%
.\"
.\"     @(#)du.1        6.18 (Berkeley) %G%
.\"
.Dd
.Dt DU 1
.Os
.Sh NAME
.Nm du
.Nd display disk usage statistics
.Sh SYNOPSIS
.Nm du
.Op Fl a Li \&| Fl s
.Op Fl Hhx
.Op Ar file ...
.Sh DESCRIPTION
The
.Nm du
utility displays the file system block usage for each file argument
and for each directory in the file hierarchy rooted in each directory
argument.
If no file is specified, the block usage of the hierarchy rooted in
the current directory is displayed.
The number of blocks are in the same units as that returned by the
.Xr stat 2
system call, i.e. 512-byte blocks.
Partial numbers of blocks are rounded up.
.Pp
The options are as follows:
.Bl -tag -width Ds
.It Fl a
Display an entry for each file in the file hierarchy.
.It Fl s
Display only the grand total for the specified files.
.It Fl H
When encountering a symbolic link on the command line, follow it.  All other
symbolic links encountered in the traversal are not followed.
.It Fl h
When encountering a symbolic link anywhere in the traversal, follow it.
.It Fl x
Filesystem mount points are not traversed.
.El
.Pp
.Nm Du
references symbolic links as the links themselves unless the
.Fl H
or
.Fl h
flags are specified, in which case behavior is as detailed above.
.Pp
Files having multiple hard links are counted (and displayed) a single
time per
.Nm du
execution.
.Sh ENVIRONMENTAL VARIABLES
.Bl -tag -width BLOCKSIZE
.It Ev BLOCKSIZE
If the environmental variable
.Ev BLOCKSIZE
is set, the block counts will be displayed in units of that size block.
.El
.Sh SEE ALSO
.Xr df 1 ,
.Xr fts 3 ,
.Xr symlink 7 ,
.Xr quot 8
.Sh HISTORY
A
.Nm du
command appeared in
.At v6 .