+itemize(
+ it() A bf(-) specifies that the file should consist of only exclude
+ patterns, with no other rule-parsing except for in-file comments.
+ it() A bf(+) specifies that the file should consist of only include
+ patterns, with no other rule-parsing except for in-file comments.
+ it() A bf(C) is a way to specify that the file should be read in a
+ CVS-compatible manner. This turns on 'n', 'w', and '-', but also
+ allows the list-clearing token (!) to be specified. If no filename is
+ provided, ".cvsignore" is assumed.
+ it() A bf(e) will exclude the merge-file name from the transfer; e.g.
+ "dir-merge,e .rules" is like "dir-merge .rules" and "- .rules".
+ it() An bf(n) specifies that the rules are not inherited by subdirectories.
+ it() A bf(w) specifies that the rules are word-split on whitespace instead
+ of the normal line-splitting. This also turns off comments. Note: the
+ space that separates the prefix from the rule is treated specially, so
+ "- foo + bar" is parsed as two rules (assuming that prefix-parsing wasn't
+ also disabled).
+ it() You may also specify any of the modifiers for the "+" or "-" rules
+ (below) in order to have the rules that are read-in from the file
+ default to having that modifier set. For instance, "merge,-/ .excl" would
+ treat the contents of .excl as absolute-path excludes,
+ while "dir-merge,s .filt" and ":sC" would each make all their
+ per-directory rules apply only on the sending side.
+)
+
+The following modifiers are accepted after a "+" or "-":
+
+itemize(
+ it() A "/" specifies that the include/exclude rule should be matched
+ against the absolute pathname of the current item. For example,
+ "-/ /etc/passwd" would exclude the passwd file any time the transfer
+ was sending files from the "/etc" directory, and "-/ subdir/foo"
+ would always exclude "foo" when it is in a dir named "subdir", even
+ if "foo" is at the root of the current transfer.
+ it() A "!" specifies that the include/exclude should take effect if
+ the pattern fails to match. For instance, "-! */" would exclude all
+ non-directories.
+ it() A bf(C) is used to indicate that all the global CVS-exclude rules
+ should be inserted as excludes in place of the "-C". No arg should
+ follow.
+ it() An bf(s) is used to indicate that the rule applies to the sending
+ side. When a rule affects the sending side, it prevents files from
+ being transferred. The default is for a rule to affect both sides
+ unless bf(--delete-excluded) was specified, in which case default rules
+ become sender-side only. See also the hide (H) and show (S) rules,
+ which are an alternate way to specify sending-side includes/excludes.
+ it() An bf(r) is used to indicate that the rule applies to the receiving
+ side. When a rule affects the receiving side, it prevents files from
+ being deleted. See the bf(s) modifier for more info. See also the
+ protect (P) and risk (R) rules, which are an alternate way to
+ specify receiver-side includes/excludes.
+)
+
+Per-directory rules are inherited in all subdirectories of the directory
+where the merge-file was found unless the 'n' modifier was used. Each
+subdirectory's rules are prefixed to the inherited per-directory rules
+from its parents, which gives the newest rules a higher priority than the
+inherited rules. The entire set of dir-merge rules are grouped together in
+the spot where the merge-file was specified, so it is possible to override
+dir-merge rules via a rule that got specified earlier in the list of global
+rules. When the list-clearing rule ("!") is read from a per-directory
+file, it only clears the inherited rules for the current merge file.
+
+Another way to prevent a single rule from a dir-merge file from being inherited is to
+anchor it with a leading slash. Anchored rules in a per-directory
+merge-file are relative to the merge-file's directory, so a pattern "/foo"
+would only match the file "foo" in the directory where the dir-merge filter
+file was found.
+
+Here's an example filter file which you'd specify via bf(--filter=". file":)
+
+quote(
+tt(merge /home/user/.global-filter)nl()
+tt(- *.gz)nl()
+tt(dir-merge .rules)nl()
+tt(+ *.[ch])nl()
+tt(- *.o)nl()
+)
+
+This will merge the contents of the /home/user/.global-filter file at the
+start of the list and also turns the ".rules" filename into a per-directory
+filter file. All rules read-in prior to the start of the directory scan
+follow the global anchoring rules (i.e. a leading slash matches at the root
+of the transfer).