zsh does a terrible job at keeping bash history in sync.

How?

(I use zsh. I also downvoted you.)

Because zsh has shared history, I'm not sure if it's enabled by default, but I use oh-my-zsh (highly recommended!) and shared history works.

Edit: How to enable in zsh: http://www.refining-linux.org/archives/49/ZSH-Gem-15-Shared-...

I suggest some of the following setopt's: APPEND_HISTORY AUTO_CD HIST_IGNORE_SPACE HIST_IGNORE_DUPS HIST_NO_STORE

AUTO_CD is nice because you can just straight-up type a directory and it'll go there (i.e. .. or tilde).

HIST_IGNORE_SPACE and HIST_NO_STORE work out nicely when you want commands not to show up, i.e. stuff where maybe your password is inline, or you're handling something sensitive.

HIST_IGNORE_DUPS just saves space. HIST_IGNORE_ALL_DUPS even more so.

He's joking that Zsh isn't Bash and therefor doesn't keep Bash's history in sync.

I think akkartik is responding to willlll (who posted "use zsh, problem solved"), not to silverstorm (who posted "zsh does a terrible job at keeping bash history in sync.").