Error in README silva reference procedure

I have attempted creating a SILVA taxonomy alignment file following the procedure in the README file that is included with the SILVA reference downloads (an online version can be viewed here http://blog.mothur.org/2015/12/03/SILVA-v123-reference-files/)

The following line of code results in an error:

grep ">" silva.full_v128.good.pcr.ng.unique.fasta | cut -f 1 | cut -c 2- > silva.full_v128.good.pcr.ng.unique.accnos

[ERROR]: You are missing (
Invalid.

Any help would be very appreciated, and I apologize if this question was posted in the wrong discussion group.

My apologies, I found the answer. By wrapping the code in systems() it runs as expected for me.