[PATCH 3/5] hier.7: Specifies the optional directories from those mentioned.

@@ -89,7 +89,7 @@ Configuration files for the X11 window system (optional).
 On machines with home directories for users, these are usually beneath
 this directory, directly or not.
 The structure of this directory
-depends on local administration decisions.
+depends on local administration decisions (optional).
 .TP
 .I /lib
 This directory should hold those shared libraries that are necessary

@@ -319,20 +319,21 @@ or
 .IR /usr/man .
 .TP
 .I /usr/share/dict
-Contains the word lists used by spell checkers.
+Contains the word lists used by spell checkers (optional).
 .TP
 .I /usr/share/doc
-Documentation about installed programs.
+Documentation about installed programs (optional).
 .TP
 .I /usr/share/games
 Static data files for games in
-.IR /usr/games .
+.I /usr/games
+(optional).
 .TP
 .I /usr/share/info
-Info pages go here.
+Info pages go here (optional).
 .TP
 .I /usr/share/locale
-Locale information goes here.
+Locale information goes here (optional).
 .TP
 .I /usr/share/man
 Manual pages go here in subdirectories according to the man page sections.

@@ -348,25 +349,25 @@ Miscellaneous data that can be shared among different architectures of the
 same OS.
 .TP
 .I /usr/share/nls
-The message catalogs for native language support go here.
+The message catalogs for native language support go here (optional).
 .TP
 .I /usr/share/sgml
-Files for SGML and XML.
+Files for SGML and XML (optional).
 .TP
 .I /usr/share/terminfo
-The database for terminfo.
+The database for terminfo (optional).
 .TP
 .I /usr/share/tmac
-Troff macros that are not distributed with groff.
+Troff macros that are not distributed with groff (optional).
 .TP
 .I /usr/share/zoneinfo
-Files for timezone information.
+Files for timezone information (optional).
 .TP
 .I /usr/src
 Source files for different parts of the system, included with some packages
 for reference purposes.
 Don't work here with your own projects, as files
-below /usr should be read-only except when installing software.
+below /usr should be read-only except when installing software (optional).
 .TP
 .I /usr/src/linux
 This was the traditional place for the kernel source.

@@ -459,21 +460,22 @@ Spooled jobs for
 .BR cron (8).
 .TP
 .I /var/spool/lpd
-Spooled files for printing.
+Spooled files for printing (optional).
 .TP
 .I /var/spool/mail
 Replaced by
 .IR /var/mail .
 .TP
 .I /var/spool/mqueue
-Queued outgoing mail.
+Queued outgoing mail (optional).
 .TP
 .I /var/spool/news
-Spool directory for news.
+Spool directory for news (optional).
 .TP
 .I /var/spool/rwho
 Spooled files for
-.BR rwhod (8).
+.BR rwhod (8)
+(optional).
 .TP
 .I /var/spool/smail
 Spooled files for the

@@ -482,7 +484,8 @@ mail delivery program.
 .TP
 .I /var/spool/uucp
 Spooled files for
-.BR uucp (1).
+.BR uucp (1)
+(optional).
 .TP
 .I /var/tmp
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