How can I fix the follow line:
for line in $(cat /root/files_to_search); do find /opt/ -iname $line -exec rm {} >> files_founded.txt ; done
The problem is that the commands of for and -exec end with a semicolon, the for command has this statement
for i in something; do command ; done (do terminate with ;)
and find statment with -exec
find /path/ -name somestring -exec command \; (-exec also finish with ;)
You don't even need to use -exec echo {} since that is default action in find. You can use this for loop:
while IFS= read -r line; do
find /opt/ -iname "$line"
done < /root/files_to_search >> files_founded.txt
There is no need to use for line in $(cat ...) either as you can read from the input using < file
See BASH FAQ on reading a file line by line
If you must use -exec in find then use:
while IFS= read -r line; do
find /opt/ -iname "$line" -exec rm {} \;
done < /root/files_to_search >> files_founded.txt