Hello, You could maybe solve the read problem by also embedding, in the name of the file, its intended content size ?
So it could be reasonably cheap to check if a file is present but not yet totally flushed to the disk by comparing its intended size (from its name) and its current real size ? For the write operation, one thing you should consider is using the file.getFileDescriptor().sync() method, that will ensure that all the content is flushed by the OS before the function responsible for writing to the file returns to its caller but before calling sync(), you must also have flushed any java buffer (e.g. calling flush() on the OutputStreams/Writers). If the file is immutable, I don't understand why you could have concurrency regarding the act of writing ? HTH, -- Laurent 2009/2/14 James Reeves <weavejes...@googlemail.com> > > Hi folks, > > I've been having some difficulty coming up with a scheme for writing > to files in a thread-safe manner. The files are named with the hash of > their content, so they are effectively immutable. > > The problem comes with writing them for the first time. I need to > ensure that while a file is initially being written, no other thread > attempts to read or write to the file. > > The best solution I've come up with so far is to write to a temporary > file, then rename the file to its hash once it has been closed. This > seems to work, but I'd be very interested to know how other people > have handled similar concurrent I/O problems in Clojure. > > - James > > > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -~----------~----~----~----~------~----~------~--~---
