Re: Filtering socklog output revisited

["George Georgalis" <george@galis.org>]

On Fri, Sep 01, 2006 at 12:51:37PM -0500, Matthew R. Dempsky wrote:
>On Fri, Sep 01, 2006 at 11:16:04AM -0400, George Georgalis wrote:
>> Seems like a good c program, read input from an arbitrary fd
>> specified as a command line switch and pipe to stdout (where
>> it can be directed to an arbitrary fd, with the shell).
>
>This sounds like a job for multitee[1].
>
>[1] http://code.dogmap.org/fdtools/multitee/

even with multitee, I need some help. :-{

Here's the goal, writing a qmail-queue replacement, which will
conditionally call qmail-queue and possibly alter the fd1 it
receives.

To test the filter, I'm doing the following:

* verify $a gets set set correctly in the test by first setting it to "null".

* spawn a sub-shell to contain all fd

* generate qmail-queue type expected input: 'message\n' to fd0 and
'envelope\x00' to fd1 (I do this by outputting them to fd1 and fd2
because I expect the target program will attach those to fd0 and fd1)

* pipe output to a separate process (sub-shell)

* in the target process, capture fd0 and fd1 so they can be
filtered and attached to qmail-queue


Trying multitee, after many failed attempts, I got to 

 a='null'; (printf "message\n"; printf "envelope\x00" >&2) | (cat >/dev/null; a="n$(multitee 1,0)"; printf "@$a\n")

I expected this output "n@envelope\x00\n" but when it didn't work I
began to wonder if I needed multitee at all...

 a='null'; (printf "message\n"; printf "envelope\x00" >&2) | (cat >/dev/null; a="n$(exec 1>&0; cat)"; printf "@$a\n")

but what I actually get is "envlope@n\n", so what's wrong here? (and what's happening?)

// George



-- 
George Georgalis, systems architect, administrator <IXOYE><