From 66b2b2612732e6782f5ed598361e0cc7ee061e7e Mon Sep 17 00:00:00 2001
From: Tom Ryder <tom@sanctum.geek.nz>
Date: Sun, 20 Nov 2016 13:51:18 +1300
Subject: Add ddup(1df)

---
 .gitignore        |  1 +
 Makefile          |  6 ++++--
 README.markdown   |  1 +
 bin/ddup.awk      |  2 ++
 foo               |  4 ++++
 man/man1/ddup.1df | 20 ++++++++++++++++++++
 6 files changed, 32 insertions(+), 2 deletions(-)
 create mode 100644 bin/ddup.awk
 create mode 100644 foo
 create mode 100644 man/man1/ddup.1df

diff --git a/.gitignore b/.gitignore
index 4e941ee3..97c59ef1 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,4 @@
+bin/ddup
 bin/han
 bin/mean
 bin/med
diff --git a/Makefile b/Makefile
index 7e00910b..2ac5804e 100644
--- a/Makefile
+++ b/Makefile
@@ -66,7 +66,8 @@ EMAIL := tom@sanctum.geek.nz
 KEY := 0xC14286EA77BB8872
 SENDMAIL := msmtp
 
-all : bin/han \
+all : bin/ddup \
+	bin/han \
 	bin/mean \
 	bin/med \
 	bin/mftl \
@@ -83,6 +84,7 @@ all : bin/han \
 
 clean distclean :
 	rm -f \
+		bin/ddup \
 		bin/han \
 		bin/mean \
 		bin/med \
@@ -181,7 +183,7 @@ install-bash-completion : install-bash
 	install -pm 0644 -- bash/bash_completion "$(HOME)"/.config/bash_completion
 	install -pm 0644 -- bash/bash_completion.d/* "$(HOME)"/.bash_completion.d
 
-install-bin : bin/han bin/mean bin/med bin/mftl bin/mode bin/rfct \
+install-bin : bin/ddup bin/han bin/mean bin/med bin/mftl bin/mode bin/rfct \
 	bin/rndi bin/sd2u bin/slsf bin/su2d bin/tot bin/unf install-bin-man
 	install -m 0755 -d -- "$(HOME)"/.local/bin
 	for name in bin/* ; do \
diff --git a/README.markdown b/README.markdown
index 13b6737e..1dd1643c 100644
--- a/README.markdown
+++ b/README.markdown
@@ -417,6 +417,7 @@ Installed by the `install-bin` target:
 *   `clrd(1df)` sets up a per-line file read, clearing the screen first.
 *   `clwr(1df)` sets up a per-line file write, clearing the screen before each
     line
+*   `ddup(1df)` removes duplicate lines from unsorted input.
 *   `dmp(1df)` copies a pass(1) entry selected by `dmenu(1)` to the X
     CLIPBOARD.
 *   `dub(1df)` lists the biggest entries in a directory.
diff --git a/bin/ddup.awk b/bin/ddup.awk
new file mode 100644
index 00000000..28b4d135
--- /dev/null
+++ b/bin/ddup.awk
@@ -0,0 +1,2 @@
+#!/usr/bin/awk -f
+!seen[$0]++
diff --git a/foo b/foo
new file mode 100644
index 00000000..d68dd403
--- /dev/null
+++ b/foo
@@ -0,0 +1,4 @@
+a
+b
+c
+d
diff --git a/man/man1/ddup.1df b/man/man1/ddup.1df
new file mode 100644
index 00000000..ca5e35a0
--- /dev/null
+++ b/man/man1/ddup.1df
@@ -0,0 +1,20 @@
+.TH DDUP 1df "November 2016" "Manual page for ddup"
+.SH NAME
+.B ddup
+\- remove duplicates from unsorted output
+.SH USAGE
+.B ddup
+FILE1 [FILE2 ...]
+.br
+.B ddup
+< FILE
+.br
+program |
+.B ddup
+.SH DESCRIPTION
+.B ddup
+removes duplicate lines from the input without requiring it to be sorted.
+Because it caches each unique line, this is less efficient than using sort(1)
+and then uniq(1), but necessary if maintaining the order is desirable.
+.SH AUTHOR
+Tom Ryder <tom@sanctum.geek.nz>
-- 
cgit v1.2.3