Deleting a command from zsh history - zsh

I'm writing a shell history application, and I'm experiencing issues with deleting a command from zsh history. When I was developing bash compatibility, I used readline to manipulate history - I first deleted command from readline's history, then wrote the history to a file. After the program exits, if the history was manipulated, then I do history -r and I get the expected behavior. Since zsh does not use readline and its history command significantly differs from the one that can be found on bash, I'm left with no other choice but to manipulate the history file directly. However, when I do that, the changes are not reflected until the shell is restarted. I have tried to use zsh's equivalent of history -r, which is supposed to be fc -R, but I did not get the expected results. While the command gets deleted from history after running that, pressing the up arrow (in order to go back to the previous command, which should be the one that invoked the program) brings me to a seemingly random command in the history.
I'd appreciate it if someone explained the odd behavior I'm experiencing. Any pointers in the right direction are also welcome.

I have solved this problem in my Zsh history editing plugin zsh-hist by not touching the histfile directly, but instead doing everything through Zsh's own mechanisms:
Set $HISTORY_IGNORE locally to a pattern that matches the contents of the entries you want to delete.
Use fc -W to write the history to file. Because of HISTORY_IGNORE, the unwanted entries will not be written.
Use fc -p to create a new history from file.
Zsh documentation:
$HISTORY_IGNORE parameter
fc builtin command

Related

Tmux asks for root password on every command

I recently had to reinstall my system and ever since I've been having a weird issue with tmux where it prompts me for my sudo password every time it creates a new pane or window (including when I first start it). It appears to make absolutely no difference whether I actually enter it or not; because the prompt happens after the pane/window was already created, I can just Ctrl-C out of the prompt if I want. I’m not sure if more functions are also affected which I just don't use but at least some of those I do use are definitely not (e.g. source-file).
On a sidenote, I also noted that since I changed my login shell to zsh after the reinstall, alias definitions in .zprofile do not carry over to interactive shells anymore, which they definitely did do under my previous system (although the file is definitely sourced as environment variables are set correctly even in the interactive shell). Maybe my shell environment got messed somehow and the tmux problem is just a side-effect of that?
Never mind, I found the issue: I was using a sudo call to start a daemon in my .zprofile, so when the interactive shell sourced that it caused a sudo prompt. I found a workaround which doesn't require sudo which solved the problem.

how to search all history command by using bck-i-search in zsh

I used zsh and when I run Ctrl-R to search history command, I can only get the command executed in this session, but can't search all the history commands.
I know there is a .bash_history file in bash to store all the history commands and we can do this search in bash.
Is there any way to do this in zsh?
Just search the history file:
% egrep <regexp> ~/.zsh_history
or
% less ~/.zsh_history
and use / command to search
Zsh does not save history to a file by default, that's why when changing session your history is removed.
You will have to put in your ~/.zshrc file the following:
HISTFILE=~/.zsh_history
HISTSIZE=10000
SAVEHIST=10000
setopt appendhistory
Alternatively to Ctrl-R you may write the first characters of the command then press ↑ key to scroll up the command lines history that starts with the written first characters up to the first usage
To search through history in all sessions, you'll need to enable several options. The zshoptions manual page has a History section that lists relevant options.
SHARE_HISTORY is one option which will share history between sessions. With this enabled, you should be able to search (using Ctrl-R or history) through commands run in this and other sessions.

ConEmu + zsh: how will keyboard shortcuts and other shell features work?

I'm trying to wrap my head around this: on Windows, I use cmder (a wrapper around ConEmu) which improves on the bare cmd.exe experience (a lot) but can also host other shells like PowerShell or Git Bash. I'd like to go more "unix-y" but still well integrated with my Windows tools. Git Bash strikes the right balance for me: I can do things like rm -rf node_modules but still run my Windows commands fine.
It's easy to get Git Bash going inside cmder, however, I'd like to replace the shell with zhs, mainly to get the super-useful "up arrow respects the current prefix" feature (I write git, press the up arrow and only get suggestions on the recent Git commands).
The question is, who will handle the up arrow? Will it be ConEmu and do Windows-y stuff (cycling through all the commands) or will it fall down to zsh and the cycling will be implemented by it? How does this work?
Related: ConEmu: possible to change the up arrow behavior?
ConEmu's disclaimer states
ConEmu is not a shell, so it does not provide "shell features" like remote access, tab-completion, command history and others.
Only the shell itself knows when user types a command and only the shell may store executed commands history. Of course, only the shell may process Up/Down/Tab keys to "browse" stored history of commands.
cmder is a bundle of tools including clink, which integrates into cmd.exe and process cmd's prompt internally. So, in cmder by default Up/Down/Tab arrows are processed by clink.
More info is here: http://conemu.github.io/en/TabCompletion.html

Weird behaviour with zsh PATH

I just encourage a weird problem with zsh today.
My environment is Mac OS X Yosemite, zsh 5.0.5 (x86_64-apple-darwin14.0)
In .zshrc, I have manually set the PATH variable to something like
export PATH="$PATH:~/.composer/vendor/bin"
Try echo $PATH in terminal, the result is as expected (contained ~/.composer/vendor/bin). Then try executing a binary from ~/.composer/vendor/bin, It'll always return me "zsh: command not found" error.
Try switching to bash, echo $PATH is also as expected, have the same result as zsh shell.
Try executing a binary from ~/.composer/vendor/bin, no problem found. Seem the PATH var is acting well on the bash shell.
What's wrong with my zsh shell?
Thanks
Try using $HOME instead of ~. In many situations, shells do not expand ~ when you expect them to and it is usually better to use $HOME. ~ is really only intended to be a short cut for interactive use. (The only case I can recall where ~ was preferred was in a .gitalias, where ~ was expanded and variables were not.)
Type rehash to pick-up $PATH changes.
From the zsh user guide:
The way commands are stored has other consequences. In particular, zsh
won't look for a new command if it already knows where to find one. If
I put a new ls command in /usr/local/bin in the above example, zsh
would continue to use /bin/ls (assuming it had already been found). To
fix this, there is the command rehash, which actually empties the
command hash table, so that finding commands starts again from
scratch. Users of csh may remember having to type rehash quite a lot
with new commands: it's not so bad in zsh, because if no command was
already hashed, or the existing one disappeared, zsh will
automatically scan the path again; furthermore, zsh performs a rehash
of its own accord if $path is altered. So adding a new duplicate
command somewhere towards the head of $path is the main reason for
needing rehash.
EDIT However #WilliamPursell could be onto something with his comment:
note that "composer" != ".composer"

Zsh wants to autocorrect a command, with an _ before it

I just started using Zsh lately for some of the integrated support in the shell prompt for my Git status etc.
When I type in:
ruby -v
to confirm the version of ruby I'm running, Zsh asks if I want to change the command to _ruby. Well after saying no at the prompt and the command completing as expected I continue to get the question at the prompt after confirming my command is correct.
I'm assuming there is a completion file or something of the sort.
Thanks
Update:
The shell is no longer trying to complete _ruby, it stopped responding after closing the shell a few times some how.
I tried to clean the file up several times but there is a "opts" variable that is 50 or more lines long and the lines are all ran together, some lines more than 150 characters. Maybe I could email an attachment to you if you still want to see it.
I sincerely apologize for the messy post.
This is command autocorrection, activated by the correct option. It has nothing to do with completion. You're seeing _ruby because zsh thinks there is no ruby command and it offers _ruby as the nearest existing match.
If you've just installed ruby, it's possible that zsh has memorized the list of available command earlier, and it won't always try to see if the command has appeared in between. In that case, run hash -rf. Future zsh sessions won't have this problem since the ruby command already existed when they started.
Sometimes, when you change your PATH, zsh forgets some hashed commands. The option hash_listall helps against this. As above, if you can force zsh to refresh its command cache with hash -rf.
You could make an alias:
alias ruby='nocorrect ruby'
It's what I did when zsh kept asking me if I meant .meteor when I typed meteor because auto-correct is still useful from time to time.
I find the autocorrect feature can get annoying at times. So I do in my ~/.zshrc,
DISABLE_CORRECTION="true"
I had the same problem even when the command is not installed.
I can solve it using the CORRECT_IGNORE variable in my .zshrc
# OPTs to enable
setopt HASH_LIST_ALL
setopt CORRECT
# Zsh variable to determine what to ignore,
# in this case everything starting with _ or .
CORRECT_IGNORE="[_|.]*"
I hope it helps to you or anyone with this issue
Sometime ago after an update, I got command auto-correction enabled which I don't want. If the same happened to you and you want to revert it, in the ~/.zshrc file you'll have make it:
# Uncomment the following line to enable command auto-correction.
ENABLE_CORRECTION="false"
or comment it as per bellow:
# Uncomment the following line to enable command auto-correction.
# ENABLE_CORRECTION="true"
Just a note, on my zsh (version 5.7.1 on macOS), the DISABLE_CORRECTION didn't work.
I saw in my .zshrc file the following two lines, which I then commented out
setopt CORRECT
setopt CORRECT_ALL
That did it for me.

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