On Wed, Mar 31, 2021 at 02:31:46AM +0700, by.sm--- via Bug reports for the GNU Bourne Again SHell wrote: > poc=whoami > $poc > python3 -c "print('!!')" > > That return 'whoami' command.
You're running into the csh-style history expansion. A lot of us simply disable it, because it's not worth the effort it takes to work around it. set +o histexpand If you insist on keeping it, and working around it, the key is to understand that single quotes will protect you, but double quotes may not. echo 'hi!' echo "hi!" The actual behavior of ! (history expansions) inside double quotes has changed across bash versions, so you may have more problems, or fewer problems, depending on your bash version. But there will never be zero problems.