grep changing the delimiter
Solution 1:
It you care just about the output, tr might work for you:
che@nok ~ $ grep cpu /proc/cpuinfo | tr '\n' ';'
cpu family : 6;cpu MHz : 800.000;cpu cores : 2;cpuid level : 10;cpu family : 6;cpu MHz : 800.000;cpu cores : 2;cpuid level : 10;
Solution 2:
Replace the zero-delimiter ('@') with a newline (\n) before grep:
cat file | tr '\00' '\n' | grep "search-string"