Your Kindle is not JailBroken, or if it is using my jailbreak, you'll need to whitelist your package name (in linkjail/etc/whitelist)
Keep in mind that unless you have a serial console plugged in, you won't actually see the echo anywhere, and the directory will be created in a temporary folder, that the updater will probably delete at the end of the update process

.
If you want to actually print something on screen, look into eips. You can check bin/libkh in any of my hacks to check how I usually use it, but basically, to print something on the bottom of the screen (on a K2/K3/K4, at least, might be slightly different on the Touch):
Code:
# Pull some helper functions for logging
_FUNCTIONS=/etc/rc.d/functions
[ -f ${_FUNCTIONS} ] && . ${_FUNCTIONS}
# Print a <= 48 characters message on the bottom of the screen (NOTE: Redirect to /dev/null to kill unavailable character & pixel not in range warning messages)
eips 1 $((${SCREEN_Y_RES} / ${EIPS_Y_RES} - 2)) "Hello world!" >/dev/null
(The 48 chars comment applies to a 10" screen in portrait mode)