First line of Unix launch script is empty, causes Exec format error with systemd

[woky]

Create very simple systemd service file in /etc/systemd/system/foo.service to start the program by the launch script (start) created by pack:

[Service]
ExecStart=/opt/foo/bin/start

Start the service: systemctl start foo

The service won't start and the following will appear in journal (journalctl -n20):

Nov 05 20:50:26 myhost systemd[291]: foo.service: Failed to execute command: Exec format error
Nov 05 20:50:26 myhost systemd[291]: foo.service: Failed at step EXEC spawning /opt/foo/bin/start: Exec format error

The problem is that the first line of the launch script is empty line. I think systemd is being correct (and perhaps strict) here. The shebang line should be the first line in the file.

Perhaps the fix could be something like this?

diff --git a/src/main/twirl/xerial/sbt/pack/launch.scala.txt b/src/main/twirl/xerial/sbt/pack/launch.scala.txt
index 632d466..1a13ffd 100644
--- a/src/main/twirl/xerial/sbt/pack/launch.scala.txt
+++ b/src/main/twirl/xerial/sbt/pack/launch.scala.txt
@@ -1,5 +1,4 @@
-@(opts:xerial.sbt.pack.LaunchScript.Opts, expandedClasspath:Option[String])
-#!/bin/sh
+@(opts:xerial.sbt.pack.LaunchScript.Opts, expandedClasspath:Option[String])#!/bin/sh
 #/*--------------------------------------------------------------------------
 # *  Copyright 2012 Taro L. Saito
 # *

[woky]

oops, duplicate of #119

[karanjamutahi]

Legend. You just saved me an hour.