find / -name "user.txt" -exec cat {} \; 2>/dev/null
find / -name "root.txt" -exec cat {} \; 2>/dev/null
Find string in each file from path
find / -type f -exec grep -iH 'string' {} \; # `-E` for regex
for i in {1..254} ;do (ping -c 1 192.168.1.$i | grep "bytes from" &) ;done