explainshell.com - cat %2Fhome%2Fmarcos%2FEvidencias%2FBulk_PC-20170427_%2Frfc822.txt %7C egrep %22%5B0-9%5D*%5B.%5D%2B%5B0-9%5D*%5B.%5D%5B0-9%5D*%5B.%5D%5B0-9%5D*%22

%2Fhome%2Fmarcos%2FEvidencias%2FBulk_PC-20170427_%2Frfc822.txt %7C egrep %22%5B0-9%5D*%5B.%5D%2B%5B0-9%5D*%5B.%5D%5B0-9%5D*%5B.%5D%5B0-9%5D*%22

concatenate files and print on the standard output

Concatenate FILE(s), or standard input, to standard output.

With no FILE, or when FILE is -, read standard input.

source manpages: cat