linux command tip - double redirection(꺽쇠) ">>"

Normally, redirection ">" is used overwrite.

= overwrite

echo 11 > ./11.log

cat ./11.log

11

echo 5 > ./11.log

cat ./11.log

5

If you use duoble redirection ">>", it works appending

= append

echo 11 > ./11.log

cat ./11.log

11

echo 5 >> ./11.log

cat ./11.log

11

5