From: matz@... (Yukihiro Matsumoto)
Date: 2003-12-09T17:00:57+09:00
Subject: Re: RCR - 'struct flock*' wrapper for rb_io_fcntl

Hi,

In message "Re: RCR - 'struct flock*' wrapper for rb_io_fcntl"
    on 03/12/09, "Ara.T.Howard" <ahoward@ngdc.noaa.gov> writes:

|> You can use pack/unpack for the purpose.
|> 
|>   require 'fcntl'        # import constants, perhaps this replaces IO#fcntl... 
|> 
|>   f = open('/tmp/foobar', 'w')
|>   flock = [Fcntl::F_RDLCK, 0, 0, 0, 0].pack("ssqqi")
|
|is this guaranteed to work:
|
|  are the offsets always the same as a struct flock* as the compiler lays them
|  out?
|
|if so, i am personally o.k with this. (thanks for the pointer!)

It works.  Perl people do similar things a lot.  But it's not
portable.

|> But still I would not deny your proposal for the sake of readability
|> and portability.  Maybe there can be functions that work similar to
|> pack_sockaddr_*() / unpack_sockaddr_*() in the socket extension.
|> pack_flock() or something.
|
|yes that sounds good if anwser to above is 'yes'

Yes, and preparing pack/unpack function, they can be portable.

							matz.