unix command : how to insert text at the cursor location via command line?

Hi,
Well my title isn't very clear I think. So to understand my goal:
I have a script "test1"

#!/bin/bash
xvkbd -text blabla

with xbindkeys, I bind F5 key in order it runs my test1 script
So when I press F5, test1 runs.

I'm under Emacs/Vi and I press F5 in order to have "blabla" be written at the cursor location.
... but I dunno why when I use it through xbindkeys, "blabla" text isn't written when I press F5 but when I release it ... and I have to release the F5 key very fast else nothing is printed.
And what is more, in firefox it is printed at the same speed as I type... lol ... to much slow ... imagine If instead of "blabla" I have a complete sentence xD

Instead of xbindkeys , I tried gnome keybindings (in metacity) directly too ... but it was even worst concerning the timing :frowning:

I didn't find a real command that would print a text at the cursor location.... instead of simulate the keyboard ... which doesn't seem to be a good idea :confused:

please , may someone know a such command or have a good idea ? ^^