Add a --sort flag to hath and document/test why it was needed after all.

[hath.git] / doc / man1 / hath.1

diff --git a/doc/man1/hath.1 b/doc/man1/hath.1
index 85978353ab0bdd6ff43dd2876d610ce561d697fe..69b362fe17079601c155d330918b91e48e61532c 100644 (file)
--- a/doc/man1/hath.1
+++ b/doc/man1/hath.1
@@ -101,21 +101,6 @@ Use the \(dqdig\(dq command to look up the PTR records for a netblock:
 4.0.41.198.in-addr.arpa. 897   IN      PTR     a.root-servers.net.
 6.0.41.198.in-addr.arpa. 900   IN      PTR     rs.internic.net.
 .fi
-.P
-Sort the \(dqreduced\(dq output:
-
-.nf
-.I $ echo \(dq192.168.0.100/24 192.167.1.200/24\(dq | hath reduced | sort
-192.167.1.200/24
-192.168.0.100/24
-.fi
-
-Sorting the output only makes sense for the \(dqreduced\(dq mode. In
-that mode, two output CIDRs cannot have same the numeric address and a
-different mask: one of them would contain the other, and the redundant
-one would be eliminated. As a result, there is no need for a special
-CIDR sort; the lexical or numerical sort provided by the \(dqsort\(dq
-utility will produce the same results as a more intelligent sort.
 .SH OPTIONS
 
 .IP \fB\-\-barriers\fR,\ \fB\-b\fR
@@ -148,7 +133,6 @@ address:
 .I $ echo x127.0.0.1x | grep -Po $(echo 127.0.0.1/32 | hath -b)
 x127.0.0.1x
 .fi
-
 .IP \fB\-\-normalize\fR,\ \fB\-n\fR
 (reduced mode only)
 
@@ -163,6 +147,28 @@ see CIDRs that you did not input in the first place being removed.
 .I $ echo 127.0.0.1/8 | hath reduced --normalize
 127.0.0.0/8
 .fi
+.IP \fB\-\-sort\fR,\ \fB\-s\fR
+(reduced mode only)
+
+Sort the output CIDRs numerically by octet. The \(dqsort\(dq utility
+doesn't understand IP addresses, so the default pipe-to-sort approach
+fails in some cases:
+
+.nf
+.I $ echo \(dq10.0.121.32/28 10.0.93.248/29\(dq | hath reduced | sort
+10.0.121.32/28
+10.0.93.248/29
+.I $ echo \(dq10.0.121.32/28 10.0.93.248/29\(dq | hath reduced | sort -n
+10.0.121.32/28
+10.0.93.248/29
+.fi
+
+That failure justifies adding the additional option to hath:
+
+.nf
+.I $ echo \(dq10.0.121.32/28 10.0.93.248/29\(dq | hath reduced --sort
+10.0.93.248/29
+10.0.121.32/28
 .SH BUGS
 
 Send bugs to michael@orlitzky.com.