<html>
<head>
<meta http-equiv="content-type" content="text/html; charset=ISO-8859-1">
</head>
<body bgcolor="#FFFFFF" text="#000000">
Hi all! I'm new to erlang for a few month. <br>
<br>
Recently I've developed a small pure erlang program, and it runs
well in the shell. Now I want to run it in the background, as a
daemon service process in the os (mine is Ubuntu 12.04 64bit with
R16B). So I googled "run erlang without shell", and google gave me
some advice:<br>
<br>
1. Using escript. -This is what erlang official faq suggested (
<meta http-equiv="content-type" content="text/html;
charset=ISO-8859-1">
<a href="http://www.erlang.org/faq/how_do_i.html">http://www.erlang.org/faq/how_do_i.html</a>).
<br>
2. erl -detached -s Module Function Args<br>
<br>
I tried both. As to #1, my escript goes to<br>
<br>
#!/usr/bin/env escript<br>
main(_) -><br>
my_supervisor:start_link(arg1, arg2).<br>
<br>
I ran it using "nohup ./my-escript &", and it didn't run my
code. =(<br>
<br>
So I went to #2. I was acknowledged that "-s" can only pass 0 or 1
argument, so I wrapped my supervisor using<br>
<br>
-module(run).<br>
-export([start/0]).<br>
<br>
start() -><br>
my_supervisor:start_link(arg1, arg2).<br>
<br>
and ran my code as "erl -detached -s run start". But this was also a
dead end. <br>
<br>
I guessed it's because the run:start/0 just returned and finished
the shell(Is it?), so I added a line to the run:start/0:<br>
<br>
-module(run).<br>
-export([start/0]).<br>
<br>
start() -><br>
my_supervisor:start_link(arg1, arg2),<br>
<b>receive after infinity -> stop end.</b><br>
<br>
And executed "erl -detached -s run start", and everything goes fine!
my_supervisor started to work without the shell!<br>
<br>
Though the problem "solved", I'm very very confused.<br>
1. Why the "magic line" solved my problem?<br>
2. What exactly is the proper or right way to run an erlang
application in the background as the command "nohup ... &" does?<br>
<br>
Thanks in advance!<br>
<br>
Michael<br>
</body>
</html>