1 files changed, 35 insertions, 0 deletions
diff --git a/md5sum.go b/md5sum.go
new file mode 100644
index 0000000..74ec106
--- /dev/null
+++ b/md5sum.go
@@ -0,0 +1,35 @@
+package shell
+
+import "crypto/md5"
+import "encoding/hex"
+import "log"
+import "io"
+import "os"
+
+func hash_file_md5(filePath string) (string, error) {
+	var returnMD5String string
+	file, err := os.Open(filePath)
+	if err != nil {
+		return returnMD5String, err
+	}
+	defer file.Close()
+	hash := md5.New()
+	if _, err := io.Copy(hash, file); err != nil {
+		return returnMD5String, err
+	}
+	hashInBytes := hash.Sum(nil)[:16]
+	returnMD5String = hex.EncodeToString(hashInBytes)
+	return returnMD5String, nil
+
+}
+
+// hash thyself:  hash_file_md5(os.Args[0])
+func Md5sum(filename string) string {
+	hash, err := hash_file_md5(filename)
+	if err == nil {
+		log.Println("shell.Md5sum() hash =", hash)
+		return hash
+	}
+	log.Println("shell.Md5sum() failed")
+	return ""
+}