On 01/9/06 06:08, "Donal K. Fellows" <donal.k.fellows@manchester.ac.uk> wrote:
Donal, are you saying that if the directory is not present it should be up to the implementation to decide what to do? I read your comment as saying that the specification should state that the directory should be created.
There are 3 cases: 1: User specifies existing directory - must not be created! 2: User specifies non-existing directry - must be created! 3: User does not specify directory. This case is up to the implementor but will probably follow one of the two patterns: 3a: Use existing "well-known" directory, e.g. $HOME. Implementation must document what directory will be chosen. 3b: Create new directory with "random" name so that jobs are isolated. Implementation must state that this will happen.
I do not believe that the behaviour of all existing batch systems is the same in case 3 FWIW; lower-level ones will tend to 3a (as it assumes less) and higher-level ones will tend to 3b (as it isolates better).
I actually believe that in the case of '2' that the implementation should raise a fault and not create the directory. First off, I don't believe that any of the existing low-level batch systems will do this creation for you, and supporting these batch systems is a primary goal of the HPC Profile. Second, I'm not a big supporter of "implied" behaviour. That is, there is a side-effect that a directory is created when this job is run. I'd prefer that a user needs to make sure the directory exists if they are specifying a working directory (using working directory seems to imply that the user knows a fair bit about the execution environment). As for 3, I agree. It's up to the implementation to document it's behaviour.
Yes, but it is still a common use case to run a job with 'home' being the working directory, or in a subdirectory relative of home. I think a way to specify that without giving the full path name isn't too much to ask.
Not sure I agree. The HPC Profile stuff is for a very restricted case.
Again ... I think it's up to the implementation to define it's behaviour if the working directory isn't specified. At this point, for the HPC Profile, I'd like to leave it at that. -- Chris