added simple command to emit byte patterns to stdout

cmd/trash/main.go

@@ -0,0 +1,36 @@
+package main
+
+import (
+	"flag"
+	"fmt"
+	"io"
+	"os"
+
+	"mcquay.me/trash"
+)
+
+var algo = flag.String("a", "caca", "algorithm to use")
+
+func main() {
+	flag.Parse()
+	var r io.Reader
+	switch *algo {
+	case "low", "00", "0", "nil", "null", "zeros":
+		r = trash.Zeros
+	case "ones", "ff", "hi":
+		r = trash.Fs
+	case "trash", "caca":
+		r = trash.Reader
+	case "hilo", "aa", "a":
+		r = trash.HiLo
+	case "lohi", "55", "5":
+		r = trash.LoHi
+	default:
+		fmt.Fprintf(os.Stderr, "unsupported algorithm: %v\ntry one of 'low', 'high', 'hilo', 'lohi', 'trash'\n", *algo)
+		os.Exit(1)
+	}
+	if _, err := io.Copy(os.Stdout, r); err != nil {
+		fmt.Fprintf(os.Stderr, "problem copying to stdout: %v", err)
+		os.Exit(1)
+	}
+}