the correct syntax to pipe maskprocessor | cudahashcat in linux?
maskprocessor is fine, you just wouldn't specify -a or -t. using the example command above, correct syntax would be:

mp64.bin -q 3 -r 4 ?d?d?d?d?d?d?d?d?d?d | cudaHashcat64.bin -m 2500 capture.hccap

However it looks like your specific issue with maskprocessor is that your Linux distribution does not ship a sufficiently new version of glibc. This is why we always recommend using Ubuntu LTS.
while the above works, thank you, I will be doing essentially a bruteforce attack. That is not what I want.

I would like to preserve my syntax (-t argument) AND have control over repetitions by using maskprocessor to fine tune markov..

Has this ever been discussed among yourselves? I'm probly not understanding the greater mechanics of it, but it seems to me a very basic thing. If I open a ticked asking atom for such an option, will it be closed in .5 seconds you think?

Anyways thanks =]
maskprocessor doesn't support markov, but statsprocessor does. However, statsprocessor does not support -q/-r. You can open a ticket on Trac to request adding -q/-r support to statsprocessor.
As I am very stupid I used
mp64.bin -q 3 -r 4 ?a?a?a?a?a?a?a?a?a?a [color=#ff6633]-o -[/color] | cudaHashcat64.bin -m 1800 admin.hash
to decrypt the admin router account. This way I occupy all the space of the hdd, where can I find and erase the "-o - generated file"? thx