From: "Ara.T.Howard" <ahoward@...>
Date: 2003-12-09T12:42:06+09:00
Subject: RCR - 'struct flock*' wrapper for rb_io_fcntl



SYNOPSIS:

  ruby's fcntl call is incomplete in that one cannot pass a 'struct flock *'
  arg as fcntl's third arg.  because of this, no posix compliant locking is
  available from within ruby.

SOLUTIONS:

  a) add a class, rb_cFlock, underneath class rb_cIO and a test in rb_io_fcntl to
    see whether it's third argument is of type rb_cFlock and retrieves the
    'struct flock *' pointer to pass through to other calls.  rb_cFlock could
    simply be a wrapper on a 'struct flock *' with methods type=, whence=, etc.

  b) create a module, fcntl, like the present one, but which does more that
  simply export the #defines from the header file


i can do either and submit a patch if some preference is expressed.


i'm hoping the usage in ruby would be as in:

  require 'fcntl'        # import constants, perhaps this replaces IO#fcntl... 
  include Fcntl

  f.open 'foobar', 'w' 
  flock = IO::Flock      # defaults: F_WRLCK, SEEK_SET, 0L, 0L

  f.fcntl F_SETLKW, flock


comments?

-a
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