zsh: SHARE_HISTORY or INC_APPEND_HISTORY breaks EXTENDED_HISTORY

Question

I would like to both share history across terminals and keep track of elapsed time for history commands. The intuitive way seems to be to use both EXTENDED_HISTORY and SHARE_HISTORY, but this sets all elapsed timestamps to 0 after restarting the shell. Is this the correct way to do it? Is it even possible?

Scenario 1: EXTENDED_HISTORY and SHARE_HISTORY

$ history -Dn | sed 's|\\n|\n      |g'
0:00  cat << EOF > ~/.zshrc
          HISTFILE=~/.zhistory-test
          HISTSIZE=100
          SAVEHIST=100
          setopt EXTENDED_HISTORY
          setopt SHARE_HISTORY # the only change compared to below
      EOF
0:00  exec zsh

0:00sleep 1

0:00  exec zsh

Scenario 2: only EXTENDED_HISTORY

$ history -Dn | sed 's|\\n|\n      |g'
0:00  cat << EOF > ~/.zshrc
          HISTFILE=~/.zhistory-test
          HISTSIZE=100
          SAVEHIST=100
          setopt EXTENDED_HISTORY
      EOF
0:00  exec zsh

0:01sleep 1

0:00  exec zsh

Scenario 3: INC_APPEND_HISTORY and SHARE_HISTORY

Same as scenario 1, but replacing SHARE_HISTORY with INC_APPEND_HISTORY seems to have the same effect.

System info

$ zsh --version

zsh 5.4.2 (x86_64-unknown-linux-musl)

$ ldd /usr/bin/zsh

        /lib/ld-musl-x86_64.so.1 (0x7f0f8b1d8000)
        libcap.so.2 => /lib/libcap.so.2 (0x7f0f8acfa000)
        libncursesw.so.6 => /lib/libncursesw.so.6 (0x7f0f8aa89000)
        libc.so => /lib/ld-musl-x86_64.so.1 (0x7f0f8b1d8000)

$ uname -a

Linux hostname 4.12.13_1 #1 SMP PREEMPT Thu Sep 14 13:15:00 UTC 2017 x86_64 GNU/Linux

$ lsb_release -d

Description:    Void Linux

Answer 1

I tested several ways of trying to share extended history between multiple terminal sessions and this is the only one that seems to work flawlessly:

setopt extendedhistory incappendhistorytime
autoload -Uz add-zsh-hook

import-history() {
  # Pop the last history list, so we don't grow the history stack endlessly
  fc -P

  # Initialize a new history list from $HISTFILE (and push it onto the 
  # history stack).
  fc -p $HISTFILE
}

# Import the history at the start of each new prompt.
add-zsh-hook precmd import-history

Now all you need to do to sync your history in any terminal session is to press Enter.

Answer 2

The only option you need is SHARE_HISTORY

Here's a video of shared history working

And here's the documentation linked + quoted

This option both imports new commands from the history file, and also causes your typed commands to be appended to the history file (the latter is like specifying INC_APPEND_HISTORY, which should be turned off if this option is in effect). The history lines are also output with timestamps ala EXTENDED_HISTORY (which makes it easier to find the spot where we left off reading the file after it gets re-written).

By default, history movement commands visit the imported lines as well as the local lines, but you can toggle this on and off with the set-local-history zle binding. It is also possible to create a zle widget that will make some commands ignore imported commands, and some include them.

If you find that you want more control over when commands get imported, you may wish to turn SHARE_HISTORY off, INC_APPEND_HISTORY or INC_APPEND_HISTORY_TIME (see above) on, and then manually import commands whenever you need them using ‘fc -RI’.