Replacing Phobos' BufferedFile

torhu Joined: 03/31/06 Posts: 69

Posted: 02/29/08 17:31:40 I'm porting some code from phobos, and have two use cases for BufferedFile? that I need a Tango way of doing. I originally expected to find classes that implement this in Tango, but I'm not sure anymore. Do I need to combine a FileConduit? and a BufferedStream? or something like that? How would I do this: 1) Output some text to a file. Don't need formatting or anything, but would like to have buffering. 2) Read lines from a text file. With buffering. I know how to use FileConduit?, TextFileInput?, LineIterator?, etc. I just need a straight forward way to add buffering. And I think my brain might be to small to fit the Tango IO package in it. So some hints would be welcome.

Author	Message
Cyborg16 Joined: 04/28/07 Posts: 54	Posted: 02/29/08 17:52:25 Well, this worked for me (for writing). I don't really understand a lot of the ideas in the IO package, but it might give you a hint: FileConduit conduit; // actual conduit; don't use directly when there's content in the buffer IBuffer buffer; // write strings directly to this (use opCall(void[]) ) // Open a conduit on the file: conduit = new FileConduit (_path, FileConduit.WriteCreate); scope(exit) conduit.close(); buffer = new Buffer(conduit); // And a buffer scope(exit) buffer.flush();
torhu Joined: 03/31/06 Posts: 69	Posted: 02/29/08 18:59:51 Something like that was what I expected, but I'm just wondering what the 'canonical' way is, before I start converting my phobos code. It also occurs to me that an example of this kind of thing is would be great to have in the docs. I know the docs are to be considered work in progress.
kris Joined: 03/27/04 Posts: 581	Posted: 02/29/08 19:20:35 torhu wrote: I'm porting some code from phobos, and have two use cases for BufferedFile that I need a Tango way of doing. I originally expected to find classes that implement this in Tango, but I'm not sure anymore. Do I need to combine a FileConduit and a BufferedStream or something like that? How would I do this: 1) Output some text to a file. Don't need formatting or anything, but would like to have buffering. 2) Read lines from a text file. With buffering. I know how to use FileConduit, TextFileInput, LineIterator, etc. I just need a straight forward way to add buffering. And I think my brain might be to small to fit the Tango IO package in it. So some hints would be welcome. A generic approach is to wrap a Buffer around a FileConduit, which gives you read/write buffering. If you want to use streams instead, then you can wrap a BufferStream around some other stream (such as FileStream): output = new BufferOutput(new FileOutput("name")); The same goes for input too. TextFileStream is quite handy, since it wraps all that up in one place.
torhu Joined: 03/31/06 Posts: 69	Posted: 02/29/08 20:57:44 How do I know if something is buffered? Like will it always be buffered it it implements the interface Buffered?
kris Joined: 03/27/04 Posts: 581	Posted: 03/01/08 05:43:28 Turns out that TextFileOutput was not buffered, which is now fixed (to match the buffered input). Thanks for bringing this up. Yes, anything implementing Buffered will perform buffered I/O
torhu Joined: 03/31/06 Posts: 69	Posted: 03/01/08 16:13:43 Thanks. The docs for Buffered only talks about sharing a buffer. I wasn't sure if it was implied that a class implementing Buffered has to perform its own buffering in case it's not coupled with a stream that is buffered. Maybe Buffer.share should be mentioned in connection with Buffered? :)
kris Joined: 03/27/04 Posts: 581	Posted: 03/02/08 21:51:42 Yes, you're right