explainshell.com - plan9-cat.1 %2Fhome%2Fmarcos%2FEvidencias%2FBulk_20170518%2Fdomain_histogram.txt %7C grep -oE %22%5Cb%28%5B0-9%5D%7B1%2C3%7D%5C.%29%7B3%7D%5B0-9%5D%7B1%2C3%7D%5Cb%22 %7C sort %7C uniq

%2Fhome%2Fmarcos%2FEvidencias%2FBulk_20170518%2Fdomain_histogram.txt %7C grep -oE %22%5Cb%28%5B0-9%5D%7B1%2C3%7D%5C.%29%7B3%7D%5B0-9%5D%7B1%2C3%7D%5Cb%22 %7C sort %7C uniq

catenate files