Unable to forward search Bash history similarly as with CTRL-r - bash

I am trying to search my bash history similarly as with CTRL-r, but to forward direction.
It has been a pain for me, when I just hit once too often CTRL-r, to find the previous command again.
How can you forward search your Bash history similarly as in reverse searching?

You can search forward as well. From the bash info manual, "8.2.5 Searching for Commands in the History":
To search backward in the history for a particular string, type C-r.
Typing C-s searches forward through the history.
The problem with Ctrl-S however is that sometimes collides with XON/XOFF flow control (in Konsole for instance). The searching is a readline feature however, and you should be able to bind it to some other key. Update: Simpler and better is just to disable XON/XOFF by running
stty -ixon

The best trick IMHO is enabling with pgup and pgdown. just put that in your ~/.inputrc
"\e[5~": history-search-forward
"\e[6~": history-search-backward
logout/login, type the first letters and then pgup or pgdown to search throughout history
ctrl-R search all lines containing words, whereas history-search-forward search lines beginning with words

You may want to try https://github.com/dvorka/hstr which allows for "suggest box style" filtering of Bash history with (optional) metrics based ordering i.e. it is much more efficient and faster in both forward and backward directions:
It can be easily bound to Ctrl-r and/or Ctrl-s

I usually press ESC in terminal, and then the >. It resets at least and then you could try click less too often CTRL+R.

Another solution is to use:
history | grep <searched expression>

As many have experienced, ctrl+s freezes (and ctrl+q unfreezes) the terminal because of software flow control (XON/XOFF flow control) and you can disable it as mentioned in the accepted answer.
Although I can't say I've really intentionally used the feature, I do want the option to be able to pause a fast moving stream of terminal text, so I didn't want to completely disable it.
So instead of turning it off, I rebound the xoff function by placing the following in my .bashrc
stty stop '^P'
Which binds xoff to ctrl+p (and ctrl+q still unfreezes). I used "p" for "pause" and this does obscure the bash previous command function previous-history. Personally I always use the up arrow key for that so it doesn't matter to me, but you could choose a different key.
This automatically frees up ctrl+s for forward-search-history

For KDE's terminal app (Konsole), you can disable flow control with XON/XOFF from settings according to THIS answer:
"in Konsole you can disable this feature, by going to Settings ->
Configure Profile -> Choose current profile -> Edit Profile ->
Advanced Tab and disable 'Enable flow control using Ctrl+S and
Ctrl+Q'"

Related

How Do I Make Backspace Send ^H In Vim?

I have a problem that is my backspace works in the terminal but not in Vim. It sent '^?' instead of '^H' and I have been trying to figure it out. I have checked my .bashrc and there is stty erase '^?' to remove the '^?' but somehow it is not working.
I have this in my .vimrc:
set backspace=indent,eol,start
set backspace=2
fixdel
This is how I would normally fix it according to my knowledge but it doesn't work in this case. I'm using xterm on Arch Linux server if that helps, I know there is a bug for xterm but I don't think that's the case. It works in Unix command but not Vim, so just the Vim that isn't working.
Any help is greatly appreciated.
Edit:
Um to clarify, I just want my backspace to delete things. My backspace doesn't delete things right now and it is giving me ^? instead of deleting. The deleting is the same as any other system that is ^H but I want to make backspace to send ^H which is delete not ^?. So instead of having to type ^H to delete, I want to do it with backspace, on MobaXterm there is a function that makes backspace to send ^H. But how do I do that on SSH?
Thanks
There's two ways to go. To the left, you see the control-H character you crave. The path that way seems clear, just a little
echo xterm.vt100.backarrowKey: true >> ~/.Xresources; xrdb ~/.Xresources
followed by either restarting all of your xterms, or pressing control and your primary mouse button on each window to bring up the menu that lets you change it per window; the menu item itself is the second one in the third section, it's right under the 8-bit controls option. That way seems to be viable. Except, beware, there's a trap door under the control-H itself, as then backspace stops working properly everywhere else except bash itself. Of course, you have part of the way out of that maze already, with your stty fu. But I kind of recall running into all sorts of other issues with that path. One of them being that the Linux console also uses ^? instead of ^H, and that's not so easy to change.
Or, the other way is to get vim to be able to do what you're trying for, using ^?. Which I think is just
:map ^V^? x
Note that I mean control-V backspace, not caret V caret question. You would also want to add this to your ~/.vimrc if that does what you need. That having been said, you didn't say exactly where in vim isn't working quite right, so it's possible you're needing a different tweak instead.

Bash Alias for Pressing Up in the Command Line

I personally hate having to go down to press the up-arrow-key when I want to repeat a command on the command line.
Is there a way to have map a bash alias to pressing the up-arrow-key? Or something that's also as convenient? I would like to just press 'n' then 'enter' instead of 'up-arrow-key' and then 'enter'
By default, bash uses the emacs keybindings. Ctrl-p and ctrl-n (for previous and next) do the same as up and down arrow.
To view and edit interactively, bash gives you the builtin bind command. help bind shows you usage, and, for example, bind -P shows you all the current bindings. Any remapping you do can be put into your .inputrc file for next time.
Also, bash provides what it calls HISTORY EXPANSION, similar to what was present in older shells. Just type !! and hit enter to execute the previous command. There's an entire section in the documentation with extra features.
Finally, I'll note that if you are repeating commands so often that hitting up-arrow enter is annoying, you might consider writing a script to do whatever you're doing.
You can issue the command set -o vi, or add it to your startup file. Then, you can hit the escape key and use the movement keys from vi to scroll. You can use k to scroll backwards, j to scroll forward, and h and `l' to move left and right.

Getting "complete" and "menu-complete" to work together

I found out that the Bash shell supports a type of autocompletion that is different from the "traditional" autocompletion, where all possibilities get listed on the following line.
With the "traditional" autocompletion, if I type ch and then press the Tab key, I get something like:
$ ch
chacl chgrp chmod chown chvt
But if I add the following line to my /etc/inputrc (which remaps the Tab key to the built-in menu-complete function):
Tab: menu-complete
then the behavior of the shell changes: the word to be completed is replaced "inline" with a single match from the list of possible completions, and if I press the Tab key again, the word gets replaced with the next match.
I found this useful, but I still wanted to keep the traditional autocompletion and have it bound to the key combination Ctrl + Tab. So I added the following line to my /etc/inputrc file, according to what the readline library documentation suggests:
Ctrl-Tab: complete
However, adding this line only seems to make both Tab and Ctrl-Tab call the traditional complete function.
Does anyone know what I am doing wrong?
Thanks in advance!
To start with, I'm not a massive expert in this area, but I think I can answer your question. First of all, while you are using Bash, Bash is a shell which interprets keyboard commands that it receives from a terminal / console. While you are informing Bash how to react to specific key combinations in the inputrc file, your Terminal determines precisely which character is 'sent' to the Shell before the inputrc file even enters the equation.
Unfortunately, on my system (granted, it's OSX - but I don't think this is strange behaviour when compared to Linux), both Tab and Ctrl-Tab send the same keyboard input to the shell. Infact, both Tab and Ctrl-Tab send a Ctrl-I command to the shell, and indeed, if I enter Ctrl-I when using the terminal, it performs the completion as if I hit Tab.
The software (installed on most Linux systems by default), showkey will tell you what keys the shell is receiving when you press specific keyboard inputs as you push them.
Anyway, my suggestion to you is to use Shift-Tab, which does appear to send it's own key-code to the shell. Shift-Tab on my computer shows up (using showkey) as '<ESC>[Z', which I think is pretty standard across the board. As such, your inputrc file with the following bindings should allow you to use shift-tab instead of ctrl-tab to achieve what you desire:
Tab: menu-complete
"\e[Z": complete
The \e in the second binding represents the escape character, and the [Z are simply the characters as shown using showkey. You can get a similar effect on OSX by simply using cat, running cat from within a terminal and pressing Shift-Tab will show you "^[[Z", where ^[ represents the escape character and the other characters are as before.
I know this doesn't resolve your question precisely, but as I don't think you are able to use Ctrl-Tab as a key combination, without re-mapping Ctrl-Tab to another keybinding within your terminal (more likely to be easier if you are using a GUI terminal), this is likely as close as you can get without significant effort!
I have ShiftTab bound to menu-complete-backward, so it goes back one step if I skipped the right completion, and I've mapped Ctrlq to complete, so if there are several possible completions I hit Ctrlq to list them without having to cycle through them.
# Make Tab cycle between possible completions
# Cycle forward: Tab
# Cycle backward: Shift-Tab
TAB: menu-complete
"\e[Z": menu-complete-backward
# Make C-q display the list of possible completions
Control-q: complete
# Display the list of matches when no further completion is possible
set show-all-if-unmodified on
Edit: Ctrlq is bound to quoted-insert by default, that is, it tells the shell to take the next key literally. quoted-insert is also bound to Ctrlv, so you don't lose that functionality if you rebind Ctrlq. Anyway, I've found that AltESC also works, by default, for showing the possible completions (as far as I can tell it is equivalent to TAB); note that it may be seized by Gnome, then either double press ESC or rebind "Switch windows directly" in Settings → Devices → Keyboard → Navigation.
The following should achieve what you're looking for (if I understand correctly!)
In your .inputrc
# display all possible matches for an ambiguous pattern at first tab
set show-all-if-ambiguous on
# next tab(s) will cycle through matches
TAB: menu-complete
# shift tab cycles backward
"\e[Z": menu-complete-backward
Where to start, if you can or cant do this is dependent your keyboard and your drivers and there isn't one catch all answer. Each key press and release generates a sequenced key pair (key down and release) (scancode) these codes are then translated by the kernel into keycodes for example on my laptop keyboard 0x3a 0xba are translated to keycode 15 (down and up) these are then translated into actions such as return letter c a / you can assign actions to keysyms using the keycode/hex/binary/octal notation which codes match which letters is determined by the kernel translation table which is fairly standardized, however the first part signal that's translated to keycodes is different for most keyboards.
Continuing with the earlier example for me shift tab (and alt and control and any combination) produce keycode 15 however in hex it produces 0x2a 0x2a 0x2a 0x2a 0x2a 0x2a 0x2a 0x2a 0x2a 0x2a 0x2a and this is because shift alt and control are special keys (modifiers) these multiply out against the keycodes and fill out the dumpkeys table the kernel is limited to the number of assignments as well this is determined by your choice of keymap and shares resources with your terminal colors (if your char set its defined above the threshold it limits your terminal color scope). And this all goes out the window if your in an xserver and has a whole new system. Most of these things can be changed,modified and manipulated by the user and programs installed. My point to all this is to emphasize that there is no catch all for the mapping of the tab key and its going to vary keyboard drivers to kbd drivers (now if you find a solution that happens to work for you excellent :)) but chances are it won't be portable and might not work if you change keyboards and might not translate between xserver and tui. What i recommend is learning the steps to modify your kbd on the go.
will give you the decimal octal hex notation for a key press on the same line
--full-table -1 >> keytable
will give you a documented with your full list of keycode->keysym pairing in a format that will give you a better picture of your layout and from there you can either use loadkey to change a keys value or ad an entry in .inputrc or your main rc file. You can also create a custom key.map file.
Further escape sequence translation is determined by the "$TERM" variable and each virtual terminal emulator can be different
infocmp "$TERM"
will give you a list of your terminal escape sequences
Resources:
https://man7.org/linux/man-pages/man4/console_codes.4.html
https://www.gnu.org/software/screen/manual/html_node/Input-Translation.html
http://kbd-project.org/docs/scancodes/scancodes.html
https://www.vt100.net/
So to sum up.
Your keyboard drivers
Your kemap choice
Your virtual terminal emulator
and your kernel
form the backbone of remapping dificult keys (tab/s-tab/a-tab)
I'm not sure Ctrl-Tab is a real character; my terminal, for instance, ignores the combination. I think the only way to use Ctrl-Tab is to use your terminal emulator to map it to some otherwise unused escape sequence, then bind that sequence to complete.

How do I switch tabs based on incremental search in vim?

For example, let's say I have three tabs open in vim:
1: nice_program.c
2: something_fun.h
3: super_script.sh
So if I hit some magic modifier key, and then type 'n' and hit enter I change tab to tab 1. Likewise, typing 'su' instead will navigate me to tab 3 instead.
Is such behavior possible? There are so many vim extensions, and I dont really get the whole vim extension lingo.
BTW, I am using gVim on XP and MacVim on OS X. Preferably the solution will work on both...
EDIT:
Note that I only want the incremental search to search across the names of the open tabs. That is, it's not supposed to actually search inside the tabs themselves.
Also, I never use buffers, it's tabs that I want this working for.
From the wording of the question it seems that you take the idea of tabs in
Vim not the way it is supposed to be taken by design of this feature. A Vim
tab page is not a form of a buffer or a window, it is a window layout
container, instead. No wonder there is no built-in way for switching to a tab
by the name of a buffer that is active (or the only one in its tab page, or
special in some other way). Semantically, that is switching to a buffer, not
a tab (but tab could be switched in order to show a buffer, if it is
necessary).
To switch to a buffer by its name use the :sbuffer command (:sb, for
short). It is not necessary to type the whole buffer name each time, since
the command has auto-completion. Usually one have to type only few letters of
a name to uniquely identify a buffer (the same way as you described
incremental search in the question).
By default, Vim open the requested buffer displacing one in the current
window. This behavior is governed by the switchbuf option. One of the
choices (called usetab) provided by that option allows to switch to a window
in another tab page if that window contains the buffer to edit. This is
exactly what suits your manner of work with tab pages.
To summarize, change the switching behavior as follows
:set switchbuf=usetab
and use the :sb command to open a buffer by typing a few letters of its name
and using Tab-completion.
I use this snippet I picked up in vim wiki to switch between open buffers (mapped to F5):
" switch between numbered buffers
:nnoremap <F5> :buffers<CR>:buffer<Space>
(put in your .vimrc file or whichever dotfile you use).
As for incremental search across open buffers, whenever I look up something using either /[something] or with */# on current word, it's automagically also highlighted in other buffers/tabs. Then I can switch buffers and hit n or N to move between matches in the currently viewed buffer. That's already baked into Vim.
Hope that helps.
The :set switchbuf=usetab solution given by ib never worked for me for whatever reason (even without loading plugins or my .vimrc) but :tab drop name-of-file works just the way you want (I found it on the Vim wiki).
Make it a custom mapping to save a few keystrokes with nnoremap <leader>t :tab drop.
Also I second ib's comment on the right and wrong way to use tabs in Vim.

How to move the cursor word by word in the OS X Terminal

I know the combination Ctrl+A to jump to the beginning of the current command, and Ctrl+E to jump to the end.
But is there any way to jump word by word, like Alt+←/→ in Cocoa applications does?
Out of the box you can use the quite bizarre Esc+F to move to the beginning of the next word and Esc+B to move to the beginning of the current word.
On macOS (all versions) the following keyboard shortcuts work by default.
ALT+F to jump Forward by a word.
ALT+B to jump Backward by a word.
Note that you have to make set the Option key to act like the Meta key. You can do this in Terminal by accessing preferences (CMD+,) and selecting Profiles -> Keyboard. In iTerm2 Pselect rofiles -> Keys -> General and select "Option key as Esc+."
Additionally some Emacs-style key bindings for simple text navigation seem to work on bash shells. You can use:
CTRL+F to move forward by a char
CTRL+B to move backward by a char
CTRL+A to jump to start of the line
CTRL+E to jump to end of the line
CTRL+K to kill the line starting from the cursor position
ALT+D to delete a word starting from the current cursor position
CTRL+W to remove the word backwards from cursor position
CTRL+Y to paste text from the kill buffer
CTRL+R to reverse search for commands you typed in the past from your history.
CTRL+S to forward search (works in ZSH for me but not bash)
Here's how you can do it
By default, the Terminal has these shortcuts to move (left and right) word-by-word:
esc+B (left)
esc+F (right)
You can configure alt+← and → to generate those sequences for you:
Open Terminal preferences (cmd+,);
At Settings tab, select Keyboard and double-click ⌥ ← if it's there, or add it if it's not.
Set the modifier as desired, and type the shortcut key in the box: esc+B, generating the text \033b (you can't type this text manually).
Repeat for word-right (esc+F becomes \033f)
Alternatively, you can refer to this blog post over at textmate:
http://blog.macromates.com/2006/word-movement-in-terminal/
Switch to iTerm2. It's free and much nicer than plain old terminal. Also it has a lot more options for customization, like keyboard shortcuts.
Also I love that you can use cmd and 1-9 to switch between tabs. Try it and you will never go back to regular terminal :)
How to set up custom keyboard preferences in iterm2
Install iTerm2
Launch and then go to preference pane.
Choose the keyboard profiles tab
You will either need to copy the profile to something new and then delete the arrow key shortcuts such as ^+ Right/Left or if you don't care about a backup just delete them from the default profile.
Next make sure your modified profile is selected (starred)
Now choose the keyboard tab (very top row)
Click on the plus button to add a new keyboard shortcut
In the first box type CMD+Left arrow
In the second box choose "send escape code"
In the third box type the letter B
Repeat with desired key combinations. escape+B moves one word to the left, escape+f moves one word to the right.
you may also wish to set up cmd+d to delete the word in front of the cursor with escape+d
I often hit the wrong button (cmd / control / alt) with an arrow key and so i have my arrow key combinations with those buttons all set to jump forward and back words, but please do what fits you best.
Actually there is a much better approach. Hold option ( alt on some keyboards) and press the arrow keys left or right to move by word. Simple as that.
option←
option→
Also ctrle will take you to the end of the line and ctrla will take you to the start.
I have Alt+←/→ working: open Preferences » Settings » Keyboard, set the entry for option cursor left to send string to shell: \033b, and set option cursor right to send string to shell: \033f. You can also use this for other Control key combinations.
Use Natural Text Editing preset!
Essentially it binds, among other key sequences, Option + LeftArrow to ^[b sequence and Option + RightArrow to ^[f
This works in fish and bash, as well as in psql terminal.
Actually it depends on what shell you use, however most shells have similar bindings. The bindings you are referring to (e.g. Ctrl+A and Ctrl+E) are bindings you will find in many other programs and they are used for ages, BTW also work in most UI apps.
Here's a look of default bindings for Bash:
Most Important Bash Keyboard Shortcuts
Please also note that you can customize them. You need to create a file, name as you wish, I named mine .bash_key_bindings and put it into my home directory. There you can set some general bash options and you can also set key bindings. To make sure they are applied, you need to modify a file named ".bashrc" that bash reads in upon start-up (you must create it, if it does not exist) and make the following call there:
bind -f ~/.bash_key_bindings
~ means home directory in bash, as stated above, you can name the file as you like and also place it where you like as long as you feed the right path+name to bind.
Let me show you some excerpts of my .bash_key_bindings file:
set meta-flag on
set input-meta on
set output-meta on
set convert-meta off
set show-all-if-ambiguous on
set bell-style none
set print-completions-horizontally off
These just set a couple of options (e.g. disable the bell; this can be all looked up on the bash webpage).
"A": self-insert
"B": self-insert
"C": self-insert
"D": self-insert
"E": self-insert
"F": self-insert
"G": self-insert
"H": self-insert
"I": self-insert
"J": self-insert
These make sure that the characters alone just do nothing but making sure the character is "typed" (they insert themselves on the shell).
"\C-dW": kill-word
"\C-dL": kill-line
"\C-dw": backward-kill-word
"\C-dl": backward-kill-line
"\C-da": kill-line
This is quite interesting. If I hit Ctrl+D alone (I selected d for delete), nothing happens. But if I then type a lower case w, the word to the left of the cursor is deleted. If I type an upper case, however, the word to the right of the cursor is killed. Same goes for l and L regarding the whole line starting from the cursor. If I type an "a", the whole line is actually deleted (everything before and after the cursor).
I placed jumping one word forward on Ctrl+F and one word backward on Ctrl+B
"\C-f": forward-word
"\C-b": backward-word
As you can see, you can make a shortcut, that leads to an action immediately, or you can make one, that just inits a character sequence and then you have to type one (or more) characters to cause an action to take place as shown in the example further above.
So if you are not happy with the default bindings, feel free to customize them as you like. Here's a link to the bash manual for more information.
Hold down the Option key and click where you'd like the cursor to move
If you happen to be a Vim user, you could try bash's vim mode. Run this or put it in your ~/.bashrc file:
set -o vi
By default you're in insert mode; hit escape and you can move around just like you can in normal-mode Vim, so movement by word is w or b, and the usual movement keys also work.
If you check Use option as meta key in the keyboard tab of the preferences, then the default emacs style commands for forward- and backward-word and ⌥F (Alt+F) and ⌥B (Alt+B) respectively.
I'd recommend reading From Bash to Z-Shell. If you want to increase your bash/zsh prowess!
As of Mac OS X Lion 10.7, Terminal maps Option-Left/Right Arrow to Esc-b/f by default, so this is now built-in for bash and other programs that use these emacs-compatible keybindings.
In Bash, these are bound to Esc-B and Esc-F.
Bash has many, many more keyboard shortcuts; have a look at the output of bind -p to see what they are.
Under iterm2's Preferences > Profile > Keys, you click the + below Key Mappings and record a new shortcut. For Action, select Send Escape Sequence and type b or f for backwards and forwards respectively.
When I tried to record one for (Ctrl+←), I noticed in the Keyboard Shortcut field that the arrow never showed up. Turns out I had to disable the default mac's System Preferences > Keyboard > Shortcuts > Mission Control shorcuts first to get things to work, as they'll override iterm2's default shortcuts. Should be true for the standard terminal app, too.
For some reason, my terminal's option+arrow weren't working. To fix this on macOS 10.15.6, I opened the terminal app's preferences, and had to set the bindings.
Option-left = \033b
Option-right = \033e
For some reason, the option-right I had was set up to be \033f. Now that it's fixed, I can freely skip around words in the termianl again.
Here's the CLI way to do so, verified it works on bash.
Add the following to your ~/.inputrc:
# macOS Option + Left/Right arrow keys to move the cursor wordwise
"\e\e[C": forward-word
"\e\e[D": backward-word
The advantage of this method is that it is terminal application agnostic - doesn't matter whether you use Terminal.app, iTerm2, or any other application.
Inspiration got from this other answer.
New answer for iTerm2 Build 3.3.4 users:
Step 1: (macOS X) System Preferences > Keyboard > Shortcuts tab > Select Mission Control (left panel) > Uncheck shortcuts that labeled as "Move left a space" and "Move right a space"
Step 2: (iTerm2 Build 3.3.4) Preferences > Profiles > Select * Default (left panel) > Keys tab > Delete both "⌥->" and "⌥<-" entries > Set both "Left Option (⌥) Key:" and "Right Option (⌥) Key:" to Esc+
No messing around with shell profiles, no messing around with inferior masOS (default) Terminal, no awkwards Esc+F/B, rinse & repeat non-sense.
Done deal!!!
Enjoy this tip, my fellow PROGRAMMERS!
As answered previously, you can add set -o vi in your ~/.bashrc to use vi/vim key bindings, or else you can add following part in .bashrc to move with Ctrl and arrow keys:
# bindings to move 1 word left/right with ctrl+left/right in terminal, just some apple stuff!
bind '"\e[5C": forward-word'
bind '"\e[5D": backward-word'
# bindings to move 1 word left/right with ctrl+left/right in iTerm2, just some apple stuff!
bind '"\e[1;5C": forward-word'
bind '"\e[1;5D": backward-word'
To start effect of these lines of code, either source ~/.bashrc or start a new terminal session.
Just check the "Use Option as meta key" option in Terminal > Preferences > Settings > [profile] > Keyboard, as mentioned here already by #cris-page.
Note however, that in macOS Catalina (10.15) and newer, zsh becomes the default shell for newly added users: its default configuration considers only whitespaces as word-boundaries, whereas the old bash makes meta-left/right jump to the nearest non-alphanumerical character (similar to B/W as opposed to b/w for those familiar with vim):
v----v- bash jumps here
$ vim some-folder/what.txt_<- jump left twice from here
^---^- zsh jumps here by default
(similar motions are true for meta-backspace as well)
There are more than one ways to make zsh command line editor navigation work similarly to bash's - here is one such method:
# Place in your profile init script, e.g. `~/.zshrc`
autoload -U select-word-style
select-word-style bash

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