This is a cross over from comp.lang.ruby



The getty is a daeamon

When I do soemthing like

#!/usr/local/bin/ruby

threads=[]

4.times do |i|
threads[i]=Thread.new do
%x{/usr/libexec/getty std.19200 tty00}
end
end
threads.each{|thr| thr.join}

I see the following
-bash-3.2$ ps -j
cd  1877 10367  1877 d6bd16c0    1 I     ph    0:00.01
/usr/local/bin/rub
cd 29342  1877  1877 d6bd16c0    1 I     ph    0:00.00
/usr/libexec/getty
cd 2773  1877  1877 d6bd16c0    1 I     ph    0:00.00 /usr/libexec/
getty
cd 30538  1877  1877 d6bd16c0    1 I     ph    0:00.01
/usr/libexec/getty
cd  6442  1877  1877 d6bd16c0    1 I     ph    0:00.01
/usr/libexec/getty

Each thread is creating a new process.

However, when I change to the same code to a program that isnt a unix
daemon

like

#!/usr/local/bin/ruby

threads=[]

4.times do |i|
threads[i]=Thread.new do
%x{/usr/local/bin/party
}
end
end
threads.each{|thr| thr.join}

I see the following
-bash-3.2$ ps -j
cd 29735 15232 29735 d6bd1d80    0 Is+   ph    0:00.06 -bash (bash)
cd 12524 29735 12524 d6bd1d80    1 T     ph    0:00.02
/usr/local/bin/rub


In this case, the thread isn't creating a process. Is getty blocking
since it's been forked 4 times, but is sleeping?

[ Post a follow-up to this message ]

On Sep 11, 8:01 pm, K-mart Cashier <cdal...@gmail.com> wrote:

> In this case, the thread isn't creating a process.

How did you establish that? Just because the process isn't running now
doesn't mean it wasn't created.

> Is getty blocking
> since it's been forked 4 times, but is sleeping?

Huh? What do you mean by "blocking"?

DS

[ Post a follow-up to this message ]

On Sep 12, 12:44 pm, David Schwartz <dav...@webmaster.com> wrote:
> On Sep 11, 8:01 pm, K-mart Cashier <cdal...@gmail.com> wrote:
> 
>
> How did you establish that? Just because the process isn't running now
> doesn't mean it wasn't created.
> 
>
> Huh? What do you mean by "blocking"?
>
> DS


I ran party and saw the following

-bash-3.2$ ps -j
USER       PID  PPID  PGID     SESS JOBC STAT  TT       TIME COMMAND
cd 28246  5443 28246 e978d8a4    0 Is+   pG    0:00.02 -bash (bash)

It shows the bash prompt, but not party. Now when I grep party, I see
the following

-bash-3.2$ ps waux | grep party
party       55  0.0  0.2   568   996 pG  S+     8:21PM    0:00.10 /usr/
local/bin/party_ (party)


Is this some kind of fork?

[ Post a follow-up to this message ]