This will enable history sharing between bash sessions in a way that the history counter does not get mixed up and history expansion like! Clear the history of the running session. The history function overrides the builtin history to make sure that the history is synchronised before it is displayed. This is necessary for the history expansion by number more about this later. Step 1 ensures that the command from the current running session gets written to the global history file.
Step 4 ensures that the commands from the other sessions gets read in to the current session history. Because step 4 will raise the history counter, we need to reduce the counter in some way. This is done in step 3. When using history expansion by number, you should always look up the number immediately before using it. That means no bash prompt display between looking up the number and using it.
Generally, once you have more than one Bash session, there is no guarantee whatsoever that a history expansion by number will retain its value between two Bash prompt displays.
If any other bash session has a new command then the history numbers of the current session will be different. I find this constraint reasonable. I have to look the number up every time anyway because I can't remember arbitrary history numbers. Running the history command piped to anything will result that command to be listed in the history twice. For example:. Commands from the current session should always be the most recent in the history of the current session.
This will also have the side effect that a given history number keeps its value for history entries from this session. I'm not aware of any way using bash. But it's one of the most popular features of zsh. Personally I prefer zsh over bash so I recommend trying it. Since they don't output any text, your prompt will be unchanged. I've done basic testing on this to ensure that it sort of works, but can't speak to any side-effects from running history -a;history -r on every prompt.
The problem is the following: I have two shell windows A and B. In shell window A, I run sleep , and without waiting for the sleep to finish in shell window B, I want to be able to see sleep in the bash history.
What this does is sort of amalgamation of what was said in this thread, except that I don't understand why would you reload the global history after every command. I very rarely care about what happens in other terminals, but I always run series of commands, say in one terminal:. You can use history -a to append the current session's history to the histfile, then use history -r on the other terminals to read the histfile.
Here's an alternative that I use. I keep a separate appended history file that I constantly update. I have the following mapped to a hotkey:. I use cat grep because it leaves the cursor at the end to enter my regex. A less ugly way to do this would be to add a couple of scripts to your path to accomplish these tasks, but hotkeys work for my purposes.
It's always nice to be able to quickly search and find that tricky regex you used or that weird perl one-liner you came up with 7 months ago. I chose to put history in a file-per-tty, as multiple people can be working on the same server - separating each session's commands makes it easier to audit. Here is my enhancement to lesmana's answer. The main difference is that concurrent windows don't share history. This means you can keep working in your windows, without having context from other windows getting loaded into your current windows.
If you explicitly type 'history', OR if you open a new window then you get the history from all previous windows. Also, I use this strategy to archive every command ever typed on my machine. You could see some commands are apparently broken: "history -n history -a".
But the good news is that it still works, because other parts still form a valid command sequence Just involving some extra cost due to executing some commands repetitively.
And not so clean. Another point to make is: there is really nothing magic. The effect is like running "ls; echo ". PS: As other users have pointed out, export is unnecessary. See: using export in. I have written a script for setting a history file per session or task its based off the following. It doesn't necessary save every history command but it saves the ones that i care about and its easier to retrieve them then going through every command.
My version also lists all history files and provides the ability to search through them all. Basically one has to store history of each session separately and recreate it on every prompt. Yes, it uses more resources, but it's not as slow as it may sound - delay starts to be noticeable only if you have more than history entries. See this gist for a full solution, including some safeguards and performance optimizations. I long wanted this, especially the ability to retrieve a command by where it was run to re-execute in a new project or find a directory by a command.
Because I prefer infinite history which saved in custom file. While I like being able to share history between terminals, especially new terminals. I would not want to share each and every command as it happens, as one window is often doing a specific task, separate form other windows.
I would have them merge on shell exit, or when I request. For a long time I looked for a way to merge bash history with timestamps , and nothing seemed acceptable to me Finally I just 'bit the bullet' and DIY'ed a script to merge, the on-disk ".
Preserving timestamp ordering, and command order within those timestamps. Now when I source this you could make it a alias or a function as you like , I use the alias 'hc'.
Adjust to suit! This is the result This is not exactly an answer to the question, or it is. It depends on how you look at it. Apparently, bash doesn't support this out of the box.
And it's not like for no reason, if you think about it. To implement this it has to write to the history file while keeping it unduplicated before executing every command, and read every time it needs history.
It only takes a minute to sign up. Connect and share knowledge within a single location that is structured and easy to search. Only when I exit my session and login again they disappear. If you want to exclude certain commands e. Ubuntu Community Ask! Sign up to join this community. The best answers are voted up and rise to the top. Stack Overflow for Teams — Collaborate and share knowledge with a private group.
Create a free Team What is Teams? Learn more. How does the history command work? Ask Question. Asked 4 years, 2 months ago. Ken has used Red Hat Linux since and has written ebooks, whitepapers, actual books, thousands of exam review questions, and hundreds of articles on open source and other topics. More about me. Relive our April event with demos, keynotes, and technical sessions from experts, all available on demand.
Enable Sysadmin. How to manage your Linux command history. Taking the mystery out of your Bash history. Image by Pete Linforth from Pixabay. The background In Bash, your command history is stored in a file. Check out these related articles on Enable Sysadmin Image. Parsing Bash history in Linux. The history command isn't always about reducing key presses.
Find out how you can leverage command history into more efficient system administration. Posted: March 30, Author: Seth Kenlon Red Hat. Using word modifiers with Bash history in Linux. So you've mastered parsing Bash history? Now you're ready to explore Bash modifiers available to the history command. Posted: April 7, Stupid Bash tricks: History, reusing arguments, files and directories, functions, and more. Here are five great tips and tricks for the Bash shell that you can use at your Linux terminal today.
Posted: June 30, Topics: Linux Linux administration Command line utilities. Ken Hess Ken has used Red Hat Linux since and has written ebooks, whitepapers, actual books, thousands of exam review questions, and hundreds of articles on open source and other topics. On Demand: Red Hat Summit Virtual Experience Relive our April event with demos, keynotes, and technical sessions from experts, all available on demand.
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