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satya71

Fortunately my memory was never good enough for me to use that facility. C-r is how I always lookup earlier commands.

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I do this too, but you know what is an even cooler and more rewarding way to exploit the shell history?

By COMMENTING your commands:

$ grep -i myname /etc/passwd # passgrep

.. ..

$ Ctrl-R "passgr"

It is so rewarding to do some intense bash work with liberal command line comments and then come back a few weeks later, "history | grep \#", and see my work notes - along with the relevant commands - available.

I used to write '~/bin' scripts for special stuff, including comments in the .sh source itself - but now it just makes more sense to wang a comment at the end of the complex/interesting commands and then just grep for the comment later ..

I have a similar system but take advantage of prefix-search rather than Ctrl+r

For commands that I reuse semi-frequently I set an environment variable so that I can easily find them with prefix searching. So for example I sometimes pin IPFS paths to Infura so I have this command in my history. I can then type pin=<Up> and recall that command (until it drops off the end of my shell history).

  pin= r curl -fiXPOST "https://ipfs.infura.io:5001/api/v0/pin/add?recursive=true&arg=$(c)"

Useful, but dangerous! I would have to check if there is already an environment variable in use before I did that ..

I know this command doesn't depend on a lowercase `pin` variable so there is no danger. Note that this doesn't change the variable in the shell, just the executed command.

Yeah, its the 'knowing beforehand' part that makes this dangerous for me. ;)

Cute trick though, will work it into my workflow and see how it feels.

IDK, environment variables get set all of the time, I rarely worry about them breaking programs. Their job is kinda to live in the background and be passed through programs so it doesn't feel like much danger. Especially when I use lowercase and almost all programs use uppercase.

But I guess everyone has a different risk level and what feels near-zero to me is meaningful to someone else.

I always add

  "\e[A": history-search-backward
  "\e[B": history-search-forward

to my .inputrc, I find it easier to use than C-r as it's some sort of autocomplete from history. But looking up commands with !number can still be very useful when you don't remember the command you need but remember when you used it (e.g. what commands you ran before and after).

What are the "\e[A" and "\e[B" do, are they key presses?

I usually do `history | grep ...` to find the command and then use it.

Non-emacs users might tend to find this surprising, but in a shell buffer you can move around with your cursor like in a text file, so after executing `history` you can search for the command as string then copy-paste it.

Yep, it binds history search to key up and key down. Start typing a command, press up or down and it will scroll through matching completions from history

https://github.com/cantino/mcfly

Life changer

Agreed. Much better than Bash's terrible built in ctrl-R which doesn't even show what you're typing if it doesn't match.

I've used build-in browser for years, but I highly recommend switching to https://github.com/junegunn/fzf for C-r in shell. Night and day boost.

Can you navigate C-r history, or are you forced to see only the last command?

You can! If you do C-r again, then it will show the next command in your history for the given search.

I've noted once within my personal bash cheat sheet this:

Search the command history

* Search as you type: Ctrl + r and type the search term; Repeat Ctrl + r to loop through results.

* Search the last remembered search term: Ctrl + r twice.

* End the search at current history entry: Ctrl + j

* Cancel the search and restore original line: Ctrl + g

Try of course at your own risk. But works for me.

Pair <C-r> with `fzf` if you want good ux.

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