From: Charles Mills <cmills@...>
Date: 2005-04-05T00:34:43+09:00
Subject: Re: Extension question


> Are there any general rules of thumb that you use when writing
extensions?

http://www.ruby-talk.org/cgi-bin/scat.rb/ruby/ruby-talk/47700

You shouldn't be able to cause your extension to seg fault from Ruby.
That may sound like a joke, but I just mean using StringValue,
NUM2LONG, etc before you starting using Ruby objects in C.

>
> My first problem was trying to figure out what should remain Ruby
code
> and what should be moved out to C.  For example, if I opened the file
> that contained binary data in Ruby, how could I "get" to that data
> using a FILE pointer in C?  Or should I just pass the filename to the
> C extension?
>
You can do either.  IMO it depends on the layout of the file.  If your
reading line by line you can do this easily using the rb_io_* functions
found in intern.h.  If your going to be moving the file position
around, using fgetc/ungetc, or reading into C structs it may be easier
to use the stdio functions directly.

-Charlie