du.1

UNIX v6源代码 这几乎是最经典的unix版本 unix操作系统设计和莱昂氏unix源代码分析都是用的该版

.th DU I 1/20/73
.sh NAME
du  \*-  summarize disk usage
.sh SYNOPSIS
.bd du
[
.bd \*-s
] [
.bd \*-a
] [ name ... ]
.sh DESCRIPTION
.it Du
gives the number of blocks contained in all files
and (recursively) directories within each specified directory or
file
.it name.
If
.it name
is missing,
`\fB.\fR'
is used.
.s3
The optional argument
.bd \*-s
causes only the grand total to
be given.
The optional argument
.bd \*-a
causes an entry to be generated
for each file.
Absence of either causes an entry to be generated for
each directory only.
.s3
A file which has two links to it is only counted once.
.sh BUGS
Non-directories
given as arguments (not under
.bd \*-a
option) are not listed.
.s3
Removable
file systems do not work correctly
since i-numbers may be repeated while the corresponding
files are distinct.
.it Du
should maintain an i-number list per root directory
encountered.