Default [Q] /sbin/echo and updater-script not playing nice...

Firstly, if this is the wrong forum, my apologies.

My problem is that I'm trying to use /sbin/echo to modify a file during a zip flash, but according to the recovery logs, all it's doing is printing the whole thing to the log. For example, if I do:

run_program("/sbin/echo", "'test' >> /sdcard/test.txt");
I don't get a new /sdcard/test.txt file with the word "test" in it, I get the output "'test' >> /sdcard/test.txt" in the log. Sorry if this is a common question, but I've been Googling without success for a couple hours now.

Thanks in advance!
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