IO like object

[Simon Kröger]

Hi List,

i have an IO like object (in this case win32 pipes, connected to a child
process). If i can provide a read and write method is there a way to get
all the other IO methods for free? (like getc, each, each_byte, print,
printf....)

cheers

Simon

 

[Alex Fenton]

Hi Simon

Nice job on finding a solution to unwanted command prompts with popen()
and backticks on win32.

Guessing this is on the same track, perhaps the standard 'stringio' library
could be used to supply IO-esque methods to string input and output from
Win32API calls?

alex

 

[Logan Capaldo]

Hi Simon

Nice job on finding a solution to unwanted command prompts with =20
popen()
and backticks on win32.

Guessing this is on the same track, perhaps the standard 'stringio' =20=

library
could be used to supply IO-esque methods to string input and output =20=

from
Win32API calls?

alex

Have you considered creating a subclass from IO and defining the =20
necessary methods?=

 

[Eric Mahurin]

On Sep 11, 2005, at 6:46 PM, Alex Fenton wrote:
=20
=20
Have you considered creating a subclass from IO and defining
the =20
necessary methods?

A module defining all other methods based on just would also
work. Then just include it.

I used both approaches for my Cursor classes (superset of IO
functionality but a different API). You would include one
module if your class defined just insert/delete (either
direction), another if it defined those plus read/write an
element (either direction), and another if you defined only
forward operations plus a skip back one element. The project
is here:

http://rubyforge.org/projects/cursor/

I guess I could add another module to include if you want to
make a cursor look like an IO. I didn't want that to be the
default because putting all this in Cursor would add a lot of
clutter as it already emulates much of the Array/String API.=20
Also the method naming in IO didn't seem appropriate for Cursor
which can handle more than just strings/characters and
symmetrically goes in both directions.



=09
__________________________________=20
Yahoo! Mail - PC Magazine Editors' Choice 2005=20
http://mail.yahoo.com

 

[Simon Kröger]

=20
=20
On Sep 11, 2005, at 6:46 PM, Alex Fenton wrote:
=20
Have you considered creating a subclass from IO and defining the =20
necessary methods?

'considered' is the right word. I just don't know which would be the=20
necessary methods. In fact (but without looking at the code yet) i realy=20
have the feeling most of them are directly mapped to the C equivalents.
If this is the case one would have to code them all from scratch.

In the meantime i figured out how to create real ruby IO objects from=20
these pipes - but this does not work on ruby < 1.8.3 :-/
(The methods are there at least since 1.6 but they state 'no such file')

BTW (and to give credits): There is a C extension on

http://rubyforge.org/projects/win32utils/

called open3 which should be able to do the same. (but i would like a=20
solution without having to start a compiler)

Conclusion: use 1.8.3 or the win32utils.
(if someone could figure out why IO.new doesn't like my pipes in ruby <=20
1.8.3 i would be happy of course)

cheers

Simon