> Not that I know of. But surely it’s only 2 lines of code, apart from error > checking and recovery?
I'd love to see those 2 lines of code! :-) But I'm concerned mainly with efficiency, as determining the next number in the naming sequence potentially can be extremely inefficient - trying 1000s of times until the next available number every time a new file needs to be written, and also every time the latest-written file needs to be retrieved. But I'm hearing this is the only way? -Carl > On Apr 16, 2016, at 2:58 PM, Quincey Morris > <quinceymor...@rivergatesoftware.com> wrote: > > On Apr 16, 2016, at 14:36 , Carl Hoefs <newsli...@autonomy.caltech.edu > <mailto:newsli...@autonomy.caltech.edu>> wrote: >> >> I have a daemon process that needs to generate a series of sequenced files >> (named sequentially, such as "file_01944576_1.dat", "file_01944576_2.dat", >> etc.) in the same directory. Does Cocoa provide a way to do this? > > Not that I know of. But surely it’s only 2 lines of code, apart from error > checking and recovery? > >> NSFileManager's -createFileAtPath:contents:attributes: method states: >> "If a file already exists at path, this method overwrites the contents of >> that file…" > > Do not use this method: it’s obsolete. Use NSData.writeToURL:options: > instead, with the NSDataWritingWithoutOverwriting option. > >> I would hate to do this blindly, such as with fstat() in a loop, because >> there will potentially be many sequences, and each can grow to an arbitrary >> number. How do Finder and other OS X agents accomplish this? > > Blindly in what sense? Even you have a lot of files, those are the files you > want. There’s nothing inherently dangerous in creating them. If you mean, > because of the possibility of conflicts with existing files, you should > follow the normal best practices inside your ‘writeToFile’ loop: > > — (Optional) Preflight the loop to ensure that conflicting files don’t exist. > This is only an approximate safety measure, since conflicting files can be > created after you check, but provides a better user experience if there is > some reasonable expectation of conflict. > > — Detect any actual conflict by the failure of ‘writeToFile’ and offer user > recovery options at that point. > _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
