implement shuf

4 files changed, 20 insertions, 1 deletions

diff --git a/.gitignore b/.gitignore
index 0c0912d..0ee44ae 100644
--- a/.gitignore
+++ b/.gitignore
@@ -9,6 +9,7 @@ nproc
 pinky
 printenv
 readlink
+shuf
 seq
 stdbuf
 tac
diff --git a/Makefile b/Makefile
index 66a0ca2..4a8a295 100644
--- a/Makefile
+++ b/Makefile
@@ -1,7 +1,7 @@
 .POSIX:
 
 PROGRAMS=arch base64 factor hostid mktemp nproc pinky printenv readlink \
-	seq stdbuf sync tac uptime users vdir yes
+	seq shuf stdbuf sync tac uptime users vdir yes
 
 all: $(PROGRAMS)
 
diff --git a/shuf b/shuf
deleted file mode 100644
index e69de29..0000000
--- a/shuf
+++ /dev/null
diff --git a/shuf.sh b/shuf.sh
new file mode 100644
index 0000000..d0fe4fb
--- /dev/null
+++ b/shuf.sh
@@ -0,0 +1,18 @@
+exec awk "$(tail -n +2 $0)" "$@"
+
+{
+	lines[NR] = $0;
+	printed[NR] = 0;
+}
+
+END {
+	nprinted = 0;
+	while (nprinted < NR) {
+		line = int(rand() * NR);
+		if (!printed[line]) {
+			print lines[line];
+			printed[line] = 1;
+			nprinted++;
+		}
+	}
+}