From: ahoward <ahoward@...>
Date: 2003-01-28T03:38:08+09:00
Subject: Re: solaris porting problem -- flock failure?

On Tue, 28 Jan 2003, ts wrote:

> >>>>> "a" == ahoward  <ahoward@fsl.noaa.gov> writes:
>
> a>   f = File.open path, 'a+'
>
>  The File is positionned at end of stream, if someone write in the file
>  when you are waiting for the lock you are not at end of stream.

tricky.

i wonder if the ruby flock impl could regonize this conditin based on the open
mode ('a' or 'a+') and do this for you... it seems like it would never be in
error.

alternatively, and probably better, a new method could be added such as
(incomplete example) :

  class File
    def File.flock_open (path, mode = 'r', flags = File::LOCK_SH)
      f = File.open path, mode
      while (not (f.flock flags))
	Thread.pass
      end
      f.seek f.size, IO::SEEK_END if mode =~ /a\+?/
      return f unless block_given?
      yield f
      f.close
    end
  end

and this method could be delegated to if File.new was called with three
arguements...

-a

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