Paul, that’s a great summary. I shall be studying it carefully. Thanks so much
Graham > On 8 Feb 2015, at 16:01, Paul Dupuis <[email protected]> wrote: > > On 2/8/2015 8:52 AM, Graham Samuel wrote: >> 6. What happens now when that downloaded instance of the app is called upon >> to save a file? Is it just saved on the local computer? If so, what if Jack >> and Jill both use the program on the same machine at different times? Will >> Jill’s files overwrite Jack’s, and if we don’t want this, how can we prevent >> it? How much work will the app itself have to do? I think I understand this >> one: the app will have to associate each file with a directory created >> especially for an individual. This is not hard, especially if Jack and Jill >> have separate user spaces - we can insist on this. But maybe these files end >> up on the server - does this ever happen? >> >> 7. While Jill is working, many others start work. Anselma downloads another >> instance of the app to her own computer. How does the original copy on the >> server know whether this is legit (not greater than the twentieth user in my >> example) or not (the 21st user), and indeed how do any of the users know the >> app is already registered? More particularly, how much work does the app >> have to do to manage this? >> >> This is really the key question - what do servers generally do to support >> multiple instances as described above? Maybe it’s nothing, in which case the >> ‘server’ version of the app will need a lot more development work than the >> version intended for a single individual; or maybe it’s so much that the app >> doesn’t need to know anything about the server once the user has done the >> download. >> > > There is a lot of variation used in serving applications. Let em run > through some of them: > > 1) The application is downloaded to the user's computer (i.e the > application's file/folder/whatever is actually copied to local disk > space on the user's computer like downloading LiveCode from the RunRev > store). In this case the application is now on the local computer and > only has access to local diskspace. Unless the "license file" was part > of the download, the app may need to be re-licensed and any file written > will be unique to that specific computer. > > 2) The server's volume (disk) containing the application is mounted > (accessed) from a local computer. Here the app remain on the server's > disk, but runs on the local computer. Files that are accessed via the > specialFolderPath function (see Livecode dictionary) in places like the > temp directory or desktop, etc. will be on the local folder, but file > accessed from the folder the app is in are on the server and shared > across users. > > 3) The application is served via an application server. A lot of > colleges and universities now use application servers such as Citrix or > Microsoft's application server software. In these instances the > application is actually run on the server and all it's files are stored > on the server, but each user gets their own "virtual" instance of the > application to their files don't conflict. Is system administrators > allow, application servers can also provide or force access to local > disk space for user files. > > 4) Also, many places may use desktop management software (such as > LanDesk or Microsoft's tools) to remotely deploy the application to > individual users computers through remote control of those computer (or > a remote "push" of software to those computers. In this case each user > ends up with their own instance of the software running on their own > computer. > > There are other ways, but most others are some variants on the > approaches above. > > _______________________________________________ > use-livecode mailing list > [email protected] > Please visit this url to subscribe, unsubscribe and manage your subscription > preferences: > http://lists.runrev.com/mailman/listinfo/use-livecode _______________________________________________ use-livecode mailing list [email protected] Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
