marlowsd at gmail.com
Wed Sep 15 06:38:17 EDT 2010
On 14/09/2010 20:00, Dimitry Golubovsky wrote:
> In the GHC I/O system, a Handle may be backed by a "device" (IODevice
> instance) with IODeviceType = Directory
> There doesn't seem to be any (at least Google search did not give
> anything) code that uses this; however, what is supposed to be read
> from such a Handle: newline-separated list of filenames (like in
> getDirectoryContents), or some sort of serialized FileStatus
> structures, or anything else?
The FD implementation of Handles never makes a Handle with an
IODeviceType of Directory, because openFile is specified to raise an
exception when applied to a directory.
So I suppose Directory could be considered superfluous in this context.
It's there because we use IODeviceType elsewhere in the IO system,
where it's important that Directory is a value (e.g. System.IO.FD.mkFD).
Alternatively we could give it a meaning as you suggest -
newline-separated file names seems like a reasonable interpretation.
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