Thanks for the detailed explanation Rajula. I think it makes perfect sense to separate working and image directories from each other. What you didn't mention is how the current working directory is resolved when an image is not started from the command line but by using the operating systems file browser (e.g. double clicking). There's also the special case of the one-click image: should the working directory be the image directory (which on OS X would be inside of the application bundle (which sucks))? Could you elaborate on that?
Cheers, Max > On 29 Jun 2017, at 14:42, Rajula Vineet <vineet.re...@iiitb.org> wrote: > > Hi all, > > As I have already been posting about my GSoC work and updates on my blog > <https://vineetreddy.wordpress.com> and on the mailing list > <http://forum.world.st/template/NamlServlet.jtp?macro=search_page&node=1294792&query=gsoc+Rajula+&days=0> > > . In this post, I would like to go in depth of my work on 'the working > directory' so that I can get valuable feedback and suggestions from > everyone. This discussion was started on an github PR > <https://github.com/pharo-project/pharo/pull/96> which was conflicting my > PR. > > Firstly, I would like to go through the current implementation of the > working directory. With this implementation, when you use the > defaultWorkingDirectory method, the directory in which the running image is > present in, is returned. This is not a completely good working because when > you run the image from a different directory like './pharo ../Pharo.image' > the working directory is the one in which your image resides. But that isn`t > your actual working directory. Due to this, > > 1. Pharo cannot be installed as a normal application in a read-only > environment. > 2. Pharo wrongly reads and writes files relative to the 'working directory'. > 3. It also makes scripting difficult. > > In the FogBugz issue here > <https://pharo.fogbugz.com/f/cases/5723/Default-Working-Directory> , there > is an example which explains the problem. > > Let say the Pharo VM and Image are in the directory "~/Pharo", > and I wrote a script in "~/Documents/Pharo-scripts" called > "perfect-numbers.st" > > I have 2 possibilities: > > cd ~/Pharo && pharo Pharo.image st > ~/Documents/Pharo-scripts/perfect-numbers.st // works > > or > > cd ~/Documents/Pharo-scripts && pharo ~/Pharo/Pharo.image st > perfect-numbers.st // doesn't work... > > It doesn't work because when pharo wants to load the file, > it tries to locate it with: FileSystem disk workingDirectory !!! > which is NOT the current working directory." > > I hope you get the problem. > > So for the new implementation <https://github.com/rajula96reddy/pharo-cli> > with the help of Guille I researched about $PWD and getcwd() for a while and > wrote a new implementation. This is how it goes > 1. I have written new methods in OSPlatorm 'getPwdFromFFI' and > 'getPwdFromFFIwithsize:'. These call the getcwd() function using the UFFI > 2. And a new method currentWorkingDirectoryPath and > currentWorkingDirectoryPathWithBufferSize: in OSPlatform which uses the > above method and gets the working directory. > 3. To integrate this, I have patched the DiskStore method > 'defaultWorkingDirectory' to use the new methods in OSPlatform. > > I have checked all the sendors of the 'defaultWorkingDirectory' for any > issue. And I also wrote some unit tests. So, the new implementation is > working fine. With this, now I am able to get the right working directory. > The example mentioned above works perfectly. > > But, there may be a few cases where it can break interoperability between > Pharo and other Smalltalk dialects like squeak etc. And the 'pharo-local' > directory and its methods should also be patched subsequently. In fact, > these problems can be tackled by running image from its own directory itself > (which is obvious ;) ) or by using the method imageDirectory in FileLocator > class explicitly when necessary. But overall a good thing is this is will > ensure the system will behave as in other languages. > > I have completed this implementation and submitted a PR > <https://github.com/pharo-project/pharo/pull/92> to github. But because of > some dependency issue, it has not yet been merged. With the help of my > mentor, I am working on the problem. > > Thanks for reading all this. Please give your feedback and comments on this > new implementation. Your suggestions help me in learning more about the > project and also about the organization. > > Thanks, > Rajula > > > > -- > View this message in context: > http://forum.world.st/The-new-implementation-of-current-working-directory-tp4952918.html > Sent from the Pharo Smalltalk Developers mailing list archive at Nabble.com. >
