MSYS - open a file as a separate process - windows

When I open a file in MSYS, i.e. subl init.js the terminal hangs until I quit that process. Is there a way to run it as a separate process like in Mac terminal?

The MSYS shell is a standard unix-like shell such as bash, so if you want to run programs in the background on the shell, you need to put an & at the end of the command. This causes it to run in the background.
I would recommend reading this SuperUser question about Shell Tutorials, which has some excellent links to shell tutorials and resources.

Related

How to save a Python 2 idle/shell/command prompt interactive session on Windows?

I run calculations on Windows for hours and would like to have the calculation report/log inside the interactive IDLE/shell window be saved to a file at the end by a command.
Would be nice to exit() and close the window too.
As much as I like Linux, this is an Unattended Windows machine, hence, some modules/commands are not available, sadly, and the ability to install other software is limited.
The fact that the developers did not think of a command to save the transactions within the IDLE/shell is surprising.
I know in some environments you can direct the output of a job, like a report to another text file by using the key -o, --o, --output, > to a text file. Surprisingly Python does not support anything like that!
Any help would be appreciated
Thanks
Windows Command Prompt supports stdout redirection and probably stderr redirection. I just tested python -c "print(test)" > F:/dev/tem/out.txt and the print out went to out.txt. Replace -c "print('test') with script.py and the same should happen. Piping stdout of one program to stdin of another might work. You might be able to chain programs with a .bat file. PowerShell likely is more powerful and flexible, but I have never used it.
I am not completely clear on what you are asking, but I hope the following answers your questions.
Python runs in 2 modes: batch and interactive. Interactive mode is intended for ephermeral interaction with a human. Batch mode is for unattended computation, with occasional screen messages, but with most results sent to a file other than the screen. Both modes are combined when you run python -i xyz.py. The file is first run in batch mode, and then Python shifts to interactive mode.
It sounds like you should be using batch mode rather than either Python's or IDLE's interactive mode. If your code runs from IDLE, you should be able to run it directly with the same python.exe that you used to run IDLE. There are exceptions, of course, if one makes one's code dependent on running within IDLE, but this is unlikely to be an accident or to be needed for unattended running.
The IDLE Shell simulates interactive Python. When a file is run from an editor window, IDLE simulates python -i file-being-edited.py, with screen output going to Shell. In either case, an interactive user can save the contents of Shell with the File => Save As menu command. So there is such a command. There are also close window and exit commands and shortcuts.
In IDLE's intended use, as an interactive python learning and program development environment, there is no need from for a program to issue these commands. To save data in a file, a program can open a file and write data directly.
Try to see if you can install Jupyter Notebook (not separate software, but just a python module)
pip install jupyter
Jupyter notebook is highly helpful for saving and sharing your code. It can be used as both a shell and as a script editor.

How would I interface with the Linux terminal (bash for windows) using windows command prompt?

I just recently found out about using bash in windows. I had alot of fun installing linux programs onto my windows computer using bash and wondered how I would be able to run an automatic script so I dont have to export my display everytime I open bash.
I used to write scripts for cmd called batch scripting and I would be able to do everything cmd could do. Now that I have access to bash, I want to script a program that connects useful pieces of cmd with useful pieces of bash but I Can't find any results telling me how to call bash commands from cmd. Thank you - Zak Kaioken

how can I run cmd in windows 10 from cygwin emacs

I am running a cygwin shell under windows 10 in which I start a "screen" session and under that the cygwin version of emacs (24). If I do M-xshell, it starts a cygwin (bash) shell just fine. So for most of my programming I'm happy. However, if within the cygwin shell I run "cmd" to get a "DOS prompt". I get this weird error message from emacs, "Waiting for process to die" (and some more text about hitting ctrl-g). I also get the same message, if I set the shell to be cmd by setting "explicit-shell-file-name" when I run shell. (That's actually what I tried first.)
Now, if hit C-g (perhaps twice?), the shell appears and cmd appears to be running, but I'm not certain of the state of things.
Has anyone else seen this error message? Googling for it returned nothing useful. Is there some incompatibility between the cygwin build of emacs and running cmd? Any hints on how to get around this problem?
Alternately, is there any way to send "builtin?" "DOS" commands (like MKLINK) under bash to a DOS box? How about running .cmd files? I really hate running a separate DOS box (not under emacs) and sometimes I need to do "DOS" things (and usually want the output captured in an emacs buffer).

`gitk` program found using the `where` command but cannot be executed?

I'm trying to run gitk on Windows but the console gives me:
'gitk' is not recognized as an internal or external command,
operable program or batch file.
But then, I can do
> where gitk
C:\Program Files (x86)\Git\bin\gitk
How comes?
UPDATE: Stealing the OP's comment:
Thanks for a (lengthy) explanation, the easiest fix for me was to move from the old msysGit (1.9.5) version to the newer "Git for Windows" builds which has a proper Windows wrapper for gitk.
gitk, unlike most git commands, is a shell script that invokes Tcl.
If you examine the gitk executable file itself, its first few lines are:
#!/bin/sh
# Tcl ignores the next line -*- tcl -*- \
exec wish "$0" -- "$#"
(At least that's what it looks like on my Linux system; the Windows installer for gitk might change that.)
On a Unix-like system, that first line, known as a "shebang", tells the system to invoke /bin/sh to execute the file rather than executing it directly.
The third line executes the wish command, which executes the script as a Tcl script.
If you have Tcl installed on your Windows system, you should be able to run gitk as a Tcl script using something like this:
C:\> tclsh "C:\Program Files (x86)\Git\bin\gitk"
(Disclaimer: I have not tried this.)
You might also be able to change the command's name from gitk to gitk.tcl and set up a file association in Windows so it will be invoked correctly. (I'm a little surprised that the Windows git installer didn't do this for you.)
More information on running Tcl scripts on Windows can be found here.
And this question discusses invoking gitk on Windows from the context menu rather than from the command line.

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.

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