Emacs ido-style shell - bash

Is there a command line shell or shell customization that supports emacs-style ido find file? In emacs, I can navigate to a directory extremely quickly using C-x C-f and (ido-mode t).
Ideally, I'm looking for a solution that can be used outside of emacs. Though I'd be open for a way to quickly change directories within an eshell buffer.

Since I also wanted something like this, I tried to implement it as a bash completion
function. Obviously it means. you have to use bash.
It is only lightly tested, so please feel free to try and report bugs /comments.
http://pgas.freeshell.org/shell/bash-ido

Try the Z-shell. It has much better completion than bash. I must admit I haven't used it for a while though and stuck with bash because it's always available.

Bash has an environment variable called CDPATH which can contain a list of directories to search when using the cd command. Also, check out the "Programmable Completion" and "READLINE" sections of the Bash manual. You should be able to cobble together something that works for you.

The best I've been able to come up with so far is autojump. Still looking for a solution closer to ido, but autojump is a great little app.

I know that some terminal emulator support extension, for instance rxvt-unicode can be extended with Perl scripts. I'm not sure since i never wrote an extension myself, but maybe what you want is doable this way.
If you want to have a look at some Perl scripts for urxvt there are some examples in /usr/lib/urxvt/perl with the default urxvt install on Debian.

If you want ido completion in eshell or similar, it might be best to write a function that uses ido to read a directory, then inserts the command to cd to that directory into the shell buffer. I don't use eshell myself, so I couldn't comment on how to actually write this function, but it's an idea.

fzf, the command-line fuzzy finder, adds fuzzy completion for bash and zsh.
According to the developer:
It's an interactive Unix filter for command-line that can be used with
any list; files, command history, processes, hostnames, bookmarks, git
commits, etc.
This is a portable solution (works on Linux, Mac, Windows), which has no dependencies.

Related

Emacs custom shell commands

Is there a possability in Emacs to run custom commands or a set of commands (eg. shell) with a user defined emacs shortcut/hook?
To make this clearer. I am working with an embedded system (target), but developing on the host. After writing and compiling code (eg using emacs compile command), I would like to copy (eg. scp) the binary to the system right away.
Furthermore it would be good if the custom shorcut/hook would be easy to adjust (eg. ip address of the target).
Btw: I am aware of the "shell-command" in emacs, but that is not quite what I am looking for.
Would appreciate any advice. Thanks!
I ended up using C-x C-f /root#my-target-ip:/tmp/myfile to edit the file directly on the target. Then you can run it with shell-command ./myfile from within emacs.

Can zsh complete command flags?

Is there some way to get zsh to complete long flag names on the command line?
$ command --reall<tab>
$ command --really-long-flag-name
Seems like a zshy thing to do.
The short answer is yes, or course it can.
To turn on zsh’s completion system, you need to do the following – probably in a startup file like your ~/.zshrc:
autoload -U compinit && compinit
On most modern Unix-like systems, once you do that you ought to find that many commands already have their flags and parameters completed, because zsh ships with a library of completion functions for common Unix commands and utilities. This library ought to be installed in a location like /usr/local/share/zsh/function (or similar, depending on your system) and consists of a bunch of scripts with filenames starting in a _ character, each of which defines the completion for a specific command.
If a command or utility you’re interested in is not yet completed correctly by zsh, you have several options:
Look into the zsh-completions package. (It may well be installable by your operating system or distribution’s package manager.)
Read the documentation for the tool you wish to have completion. Many Unix utilities ship with completion scripts for bash and/or zsh, or with some way of generating completion scripts.
If all else fails, read the documentation on zsh’s completion system (or find a good book or online tutorial) and write it yourself. This can — obviously — be non-trivial!
Reading that zsh documentation might also show you how to do other things that you may not even know yet that you want, like turning on menu-based completion.

What is the Bash file extension?

I have written a bash script in a text editor, what extension do I save my script as so it can run as a bash script? I've created a script that should in theory start an ssh server. I am wondering how to make the script execute once I click on it. I am running OS X 10.9.5.
Disagreeing with the other answers, there's a common convention to use a .sh extension for shell scripts -- but it's not a useful convention. It's better not to use an extension at all. The advantage of being able tell that foo.sh is a shell script because of its name is minimal, and you pay for it with a loss of flexibility.
To make a bash script executable, it needs to have a shebang line at the top:
#!/bin/bash
and use the chmod +x command so that the system recognizes it as an executable file. It then needs to be installed in one of the directories listed in your $PATH. If the script is called foo, you can then execute it from a shell prompt by typing foo. Or if it's in the current directory (common for temporary scripts), you can type ./foo.
Neither the shell nor the operating system pays any attention to the extension part of the file name. It's just part of the name. And by not giving it a special extension, you ensure that anyone (either a user or another script) that uses it doesn't have to care how it was implemented, whether it's a shell script (sh, bash, csh, or whatever), a Perl, Python, or Awk script, or a binary executable. The system is specifically designed so that either an interpreted script or a binary executable can be invoked without knowing or caring how it's implemented.
UNIX-like systems started out with a purely textual command-line interface. GUIs like KDE and Gnome were added later. In a GUI desktop system, you can typically run a program (again, whether it's a script or a binary executable) by, for example, double-clicking on an icon that refers to it. Typically this discards any output the program might print and doesn't let you pass command-line arguments; it's much less flexible than running it from a shell prompt. But for some programs (mostly GUI clients) it can be more convenient.
Shell scripting is best learned from the command line, not from a GUI.
(Some tools do pay attention to file extensions. For example, compilers typically use the extension to determine the language the code is written in: .c for C, .cpp for c++, etc. This convention doesn't apply to executable files.)
Keep in mind that UNIX (and UNIX-like systems) are not Windows. MS Windows generally uses a file's extension to determine how to open/execute it. Binary executables need to have a .exe extension. If you have a UNIX-like shell installed under Windows, you can configure Windows to recognize a .sh extension as a shell script, and use the shell to open it; Windows doesn't have the #! convention.
You don't need any extension (or you could choose an arbitrary one, but .sh is a useful convention).
You should start your script with #!/bin/bash (that first line is understood by execve(2) syscall), and you should make your file executable by chmod u+x. so if your script is in some file $HOME/somedir/somescriptname.sh you need to type once
chmod u+x $HOME/somedir/somescriptname.sh
in a terminal. See chmod(1) for the command and chmod(2) for the syscall.
Unless you are typing the whole file path, you should put that file in some directory mentioned in your PATH (see environ(7) & execvp(3)), which you might set permanently in your ~/.bashrc if your login shell is bash)
BTW, you could write your script in some other language, e.g. in Python by starting it with #!/usr/bin/python, or in Ocaml by starting it with #!/usr/bin/ocaml...
Executing your script by double-clicking (on what? you did not say!) is a desktop environment issue and could be desktop specific (might be different with
Kde, Mate, Gnome, .... or IceWM or RatPoison). Perhaps reading EWMH spec might help you getting a better picture.
Perhaps making your script executable with chmod might make it clickable on your desktop (apparently, Quartz on MacOSX). But then you probably should make it give some visual feedback.
And several computers don't have any desktop, including your own when you access it remotely with ssh.
I don't believe it is a good idea to run your shell script by clicking. You probably want to be able to give arguments to your shell script (and how would you do that by clicking?), and you should care about its output. If you are able to write a shell script, you are able to use an interactive shell in a terminal. That it the best and most natural way to use a script. Good interactive shells (e.g. zsh or fish or perhaps a recent bash) have delicious and configurable autocompletion facilities and you won't have to type a lot (learn to use the tab key of your keyboard). Also, scripts and programs are often parts of composite commands (pipelines, etc...).
PS. I'm using Unix since 1986, and Linux since 1993. I never started my own programs or scripts by clicking. Why should I?
just .sh.
Run the script like this:
./script.sh
EDIT: Like anubhava said, the extension doesn't really matter. But for organisational reasons, it is still recommended to use extensions.
I know this is quite old now but I feel like this adds to what the question was asking for.
If your on a mac and you want to be able to run a script by double clicking it you need to use the .command extension. Also same as before make file executable with chmod -x.
As was noted before, this isn't really that useful tbh.
TL;DR -- If the user (not necessarily the developer) of the script is using a GUI interface, it depends on what file browser they are using. MacOS's Finder will require the .sh extension in order to execute the script. Gnome Nautilus, however, recognizes properly shebanged scripts with or without the .sh extension.
I know it's already been said multiple times the reasons for and against using an extension on bash scripts, but not as much why or why not to use extensions, but I have what I consider to be a good rule of thumb.
If you're the type who hops in and out of bash and using the terminal in general or are developing a tool for someone else who does not use the terminal, put a .sh extension on your bash scripts. That way, users of that script have the option of double-clicking on that file in a GUI file browser to run the script.
If you're the type who primarily does all or most of your work in the terminal, don't bother putting any extension on your bash scripts. They would serve no purpose in the terminal, assuming that you've already set up your ~/.bashrc file to visually differentiate scripts from directories.
Edit:
In the Gnome Nautilus file browser with 4 test files (each with permissions given for the file to be executed) with stupidly simple bash command to open a terminal window (gnome-terminal):
A file with NO extension with #!/bin/bash on the first line.
It worked by double-clicking on the file.
A file with a .sh extension with #!/bin/bash on the first line.
It worked by double-clicking on the file.
A file with NO extension with NO #!/bin/bash on the first line.
It worked by double-clicking on the file...technically, but the GUI gave no indication that it was a shell script. It said it was just a plain text file.
A file with a .sh extension with NO #!/bin/bash on the first line.
It worked by double-clicking on the file.
However, as Keith Thompson, in the comments of this answer, wisely pointed out, relying on the using the .sh extension instead of the bash shebang on the first line of the file (#!/bin/bash) it could cause problems.
Another however, I recall when I was previously using MacOS, that even properly shebanged (is that a word?) bash scripts without a .sh extension could not be run from the GUI on MacOS. I would love for someone to correct me on that in the comments though. If this is true, it would prove that there is a least one file browser out there where the .sh extension matters.

How to configure bash completion to expand partial path like in emacs "minibuffer-complete"?

I would like to configure my bash shell to expand partially entered tree structure like it does emacs "minibuffer-complete" command.
Imagine I have two folders, foo1 and foo2. foo1 contains a subfolder sub1, and foo2 contains subfolder wow. So I have:
foo1/sub1/
foo2/wow/
Now when opening a file in emacs if I type
f/w
and press TAB it will automatically expand it to "foo1/wow/".
I would like to have a similar functionality in bash. Any ideas?
Whilst I don't know how to do this in bash, or even if it's possible, I know that if you change your shell to zsh, it can be done.
It's not enabled by default, and I'm not sure how to enable it either, but I use the zsh grml config, which enables the kind of expansion you're talking about.
Zsh, especially combined with said config, also has many other helpful features.
If you're not willing to change shell, then this isn't a helpful answer I'm afraid.
you can have it the other way around, using emacs M-x shell command. It open a Shell buffer with an autocompletion like in the minibuffer
Disclosure: I am the author of the project
I have written the completion functions necessary to enable such completion in bash: https://github.com/sio/bash-complete-partial-path
Hope you'll find this project useful

Windows/cygwin shebang line

I am using Sphinx quite often. There is one index that calls a stored procedure with one param as input. The param can be any number from 1 to 10 and each returs different results. Since it would make sphinx config quite crowded, even with inheritance. So I thought I will use shebang line at the start of sphinx config file (stored as sphinx.py now). This works great in production enviroment since it runs on Ubuntu. But I want to run it on my local machine as well, but here is the problem called - Windows. Since I have cygwin as well, I tried to run it via cygwin, but it is the same - nothing happens.
I tried to run with both cygwin paths and windows paths, but both get ignored or treated as comments. From what I have read it should be working with cygwin. Could it be that it does not work since I have to call an exe file?
With:
$ ./indexer.exe sphinx.conf
I have tried to run it as perl script, bash script (via cygwin) and it gets ignored either way.
Is there a reliable way to run shebang lines on Windows? Or force cygwin to at least spit an error in my face... Even hacks are good since its just my development machine.
Any help is appreciated
All a shebang line does is tell the unix system() call what interpreter to use. If you specify indexer.exe then you are saying that you want it to use indexer.exe, so that is what it will use.
If you run Indexer.exe, indexer.exe will decide what to do.
Does Indexer.exe understand shebang lines? Or not?
Perl, as a convenience, will read the shebang line, and if it isn't Perl, it will and call the other program for you.
So maybe call Perl instead of Indexer, and it will do the right thing?

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