Re: parallel: This should not happen. You have found a bug.

[Ole Tange]

On Sun, Aug 11, 2013 at 12:28 AM, Linda Walsh <gnu@tlinx.org> wrote:

> I was trying to gunzip a bunch of small files ;
> tried
>
> for i in *.gz;do
> sem -j6 $i
> done

You seem to have forgotten gunzip:

  for i in *.gz;do
    sem -j6 gunzip $i
  done

This ought to work just fine.

Personally I hate introducing an unneeded variable, so I would write it as:

  parallel gunzip ::: *gz

but your solution should work, too.

> so then tried putting the sem in background

That would be wrong and can explain why you get fork-failed later: It
needs to be able to block if 6 jobs are already running.

> If you get the error on smaller/fewer files, please include those instead.
> parallel: This should not happen. You have found a bug.
> Please contact <parallel@gnu.org> and include:
> * The version number: 20130122
> * The bugid: Can't open semaphore file
> /home/law/.parallel/semaphores/id-2fdev2fcons1.lock: Permission denied

Why is GNU Parallel not allowed to create
/home/law/.parallel/semaphores/id-2fdev2fcons1.lock?

This is explains what you see and is most likely the reason for the
failure you see.

Can you create the file by hand:

  echo > /home/law/.parallel/semaphores/id-2fdev2fcons1.lock

What OS is Perl running on and what file system is /home/law/.parallel
hosted on?


/Ole