Question

Sometimes I try to search some command by CTRL+R and it’s not found,
while I recently used it or search by CTRL+R with success.

Afer I run `history I’m able to find the command again.

Is this behavior is normal?
How it can be changed?

Answer 1

Ctrl+R searches backward from the current position in the history, so if you already moved that position you’ll miss the parts toward the end.

e.g.:

themel@kallisti: ~ $ foob
bash: foob: command not found
themel@kallisti: ~ $ barz
bash: barz: command not found
themel@kallisti: ~ $ barq
bash: barq: command not found
themel@kallisti: ~ $ quarg
bash: quarg: command not found

Ctrl+R,bar yields:

(reverse-i-search)`bar': barq

but also moves to that point in history – if you subsequently do Ctrl+R and search for quarg, you won’t find it. This is reset by remedied by using end-of-history (M-> by default) to re-set the index.