This is a very silly question...
I have a doubt regarding the ruby installation. Will the ruby be installed in a windows server if we copy the Ruby187 folder from another server and add that in the PATH of the environment variable?
Or Do we need to install the Ruby from the installer always, in order to install it ?
Thanks in advance
I actually did something similar to this yesterday at work. A fellow co-worker, who does not have Ruby installed on their system, needs the ability to run my scripts while I am on vacation. So, I copied the entire Ruby folder from my C: to a shared network drive.
You will not only have to add the path to the Ruby folder to your PATH variable but you also may want to associate the Ruby extension .rb with Ruby. Not needed but just a thought.
One issue I ran into was here at work we don't have permission to alter our PATH variable manually. So, in order for my co-worker to launch the scripts I needed ran, I wrote a small C++ app that merely run a command line call to the Ruby interpreter and then to the script to run.
So, in short, yes, it is possible. =)
EDIT: In regards to why you would add the path to the Ruby installation to the PATH variable, it is so you can call Ruby from the command line with simply C:\>ruby some_script.rb. Without that added to your PATH, you'd need to type the entire path every time like C:\>C:\ruby192\bin\ruby some_script.rb. However, you'd still need to type "ruby" first.
In regards to the association of ".rb" files to the Ruby Interpreter, it is an option while installing Ruby on Windows using the installer provided at ruby-lang.org. With that, you would not need to type "ruby" before the script name on the command line. C:\>some_script.rb would work. I don't know exactly how to do this with a network version of Ruby but one way might be to right-click on a ".rb" file, choose "Open with..." and locate the Ruby.exe file in \ruby192\bin\ruby.exe.
I hope that explains what you were asking about in the comments.
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I decided recently that I want to start learning to code. I chose python as my first language because of it's versatility and Open Source connections. Now, of course to learn any programming language, first you have to be able to practice with it by writing code and running it.
I have Python beginner tutorials I am using but as soon as I got to the point where I wanted to run a simple Hello World message, I couldn't figure out how to get my document to actually RUN. I downloaded LiClipse with the hopes of using PyDev. I read that you can run a code directly from PyDev.
Wow, what a confusing mess! I downloaded the instant install version of LiClipse and I had to manually update the pip because it was out of date and that took an hour of research all on it's own to figure out how to do it.
Now that I have the interpreter set up correctly with the most recent pip...(I THINK), when I try to run any code I write, it doesn't let me. It wants me to save it first, which of course is quite logical. But when I try to save it, it says there is no folders to save to. How can there be no folders? I have been reading the install help, but it doesn't say anything about this issue. Or maybe it did explain how to fix this issue and I simply didn't understand all the jargon included in the configuration documentation. It kept instructing me to do technical things I couldn't understand.
Can anyone tell me what is going on? Shouldn't this all be ready to go when I used the "instant install" ?? I am just a beginner here, I don't know all this technical installation jargon. If anyone can help me get this setup, please let me know.
I really want to start learning. But I can't if I don't have the right tools.
Yeah, the technical jargon can be really confusing in the beginning. I've never heard of LiClipse but I can give you a few tips to get started:
Use a good IDE or Editor. For beginning VsCode with the Python PlugIn is quite good. You can also use PyCharm (the free version is enough) but that IDE is quite confusing.
Get comfortable with the commandline. On Windows you can invoke Python by running py on Linux with python3. You open the commandline on Windows by opening the startmenu, entering cmd and hitting enter.
You will have to make sure Python is in your "PATH" enviroment variable. That is a variable telling the Operating System where to find your programms. It should have asked you whether you want to add Python to your PATH during the install.
You run your python programm by saving it as a .py file and running py <filename.py> or python3 <filename.py> on Windows or linux respectively. You have to be in the directory where you saved your file of course.
I hope I could help you. Please mark this answer as accepted if it did answer your question or helped you with your issue.
I want to start by saying I'm mainly experienced in C & C++, not Python, but with programming in general many of the concepts carry over. I also don't have enough rep to comment, or I'd ask for some clarification on how familiar you are with the commandline.
I'm going to assume you're on Windows since you didn't mention the platform.
I wrote this like a tutorial, because I found those to be very helpful when I first started programming.
I can't recommend this enough, start off by using the commandline!
I think you complicated things more by searching for a text editor that can also run code. In order to get something like that working for your setup you need to know what's happening behind-the-scenes first.
Once you have a grasp of how to write & execute Python code, then you can move on to an IDE or advanced text editor like Visual Studio Code or LiClipse with confidence.
R+Click on the Start Menu, then click on Windows PowerShell to open a terminal.
Take a moment to note the filepath shown before the blinking cursor.
This is known as the Working Directory, which works similar to how the file explorer only allows you to "view" one directory at any given time; You can open multiple explorer windows side-by-side, but you can't view multiple directories at the same time in a single window.
You can run commands by typing them and pressing Enter.
You can also use the Tab key to autocomplete things like directory/file names, commands, etc. after typing a few characters.
Now let's create a workspace directory for your first project.
This can be anywhere that you choose, but for the sake of simplicity I'll be using my User directory which is usually where PowerShell will start by default.
To create a new directory named _workspace, use the mkdir (Make Directory) command like so:
mkdir _workspace
Now let's change our working directory to _workspace by using the cd (Change Directory) command like so:
cd _workspace
This directory is empty, but if you want to view the contents of a directory you can use the ls (List Directory) command:
ls
Since this is an empty directory, nothing will happen.
Next, we'll create a Python script file using the touch command, which creates empty files:
touch HelloWorld.py
Now that we have a script file, open HelloWorld.py in Notepad by running this command:
notepad HelloWorld.py
If you use a dark desktop theme, now is the time when your retinas may be seared out by the intensity of Notepad's white color scheme.
Now, let's add the code to print "Hello World!" in Python:
print("Hello World!")
Once you're done, you can save & close Notepad to save your retinas.
Now it's time to run the program! In the PowerShell window, enter this command:
py HelloWorld.py
which will show:
Hello World!
If you see an error saying this:
The term 'py' is not recognized as the name of a cmdlet, function, script file, or operable program.
You should re-install Python and make sure you check this box in the installer:
After re-installing Python and checking the Add to PATH box, close and reopen the PowerShell window, enter the cd _workspace command again, followed by py HelloWorld.py, which should be successful this time.
I hope I could be of some help, if so, I'd greatly appreciate marking this answer as accepted so I can write comments. Happy coding!
If you are using Linux following will work.
Install python3 first (Its better to stuck on python3 now. Once you get use-to then you can code in python2.7 also.)
Open a terminal, go the folder contains your code. If your source code is in hello.py then type python3 hello.py on terminal. It will execute and print the output on terminal.
The suggestions given by both #radj and #C. Dautermann are excellent.
Like others here, I will be assuming that you are on Windows.
Before jumping into LiClipse and PyDev, I highly recommend making sure that Python and packages (such as pip) are functioning on their own first. Command line is a great tool for this.
Windows Command Line can be accessed in a variety of ways, one of which is to go to your start menu and search "cmd." Command Prompt should return. In the command prompt, run the following:
python
This should return the version of Python installed on your machine if it is configured properly. For example, you may see the following:
Python 3.10.1 (...)[...] on win32
If this does not appear, I recommend uninstalling Python and reinstalling. In the installer, you will want to check the "Add Python ... to PATH" option. This will configure your environment variables on your machine. If you plan on running multiple versions of Python down the road, don't worry; you can use batch files to set the PATH variable to another version.
Once you have Python working, your command prompt will lead with the following:
>>>
Notice that there is no longer a file path followed by >>. This is because you are now in the Python interpreter. Congratulations!
To exit the Python interpreter, enter Ctrl+Z. It should appear as the following:
^Z
After we know Python works, we will check to see that pip works. Ensure you have pip installed by entering the following:
python -m pip --version
You should then be able to see the pip version. For example:
pip 22.0.3 from C:\...
If pip is not working, you can consult this documentation on pip to make sure pip gets installed properly.
Once pip is working, again, congratulations! You've gotten over some of the biggest hurdles. At this point, you can open up any text editor, type in:
print('Hello World!')
save the file with the extension .py, then run the script through command prompt. To run a script through the command line, you have to cd to the file location, then run the script with python, like so:
cd filepath
python filename.py
Where filepath is the path to the Python file and filename is the name of the file. For example:
cd C:\Users\name\Documents\PythonPractice
python helloworld.py
Usually, command line is all that is needed when starting out with Python outside of a text editor. Notepad comes standard on Windows computers, but there are plenty of other editors out there. Sublime text and Notepad++ are some of my favorites, personally.
Now, if you're able to run everything prior, the good news is that your Python and pip are both working, and you have everything you need to get started learning Python. If Python and/or pip are not functioning, there's thankfully a huge body of troubleshooting tips out there.
Unfortunately, from what I get of your initial post, you might be struggling with configuring LiClipse. I personally do not use LiClipse, nor do I use PyDev, so my help at this point may be limited. You may want to uninstall and reinstall after confirming your Python and pip work as a first step. After that, perhaps check that you are following the practices outlined in the LiClipse manual. Worst case scenario, you can try a different version of Python (I believe it has some Python3 incompatibilities), try running PyDev independent of LiClipse, or look at a different tool. If you believe the problem lies with file locations/existence, I would look at radj's post or play around in File Explorer to see what is going on for yourself.
Again, to get familiar with Python, you don't even need these extra tools. All you need is a text editor and the command line to get started.
Some other tools to help you get started:
PyPI
A venv virtual environment tutorial
PyDev
A comparison of LiClipse alternatives in case you continue to struggle
Hope this helps. Happy Coding!
I am trying to auto compile my less files on centos.
Is it possible in ruby to watch a directory for changes to files ending in a specific extension and then execute a command when that happens?
I have tried inotify in a simple shell script but there are always problems when an ide creates temporary files etc.
You want inotify. A Ruby wrapper, rb-notify, is available.
The ZenTest gem includes the autotest command-line tool, which watches a test directory and runs tests when one of the files changes.
Go look at how that tool works. Using inotify is helpful but not necessary.
The basic idea for this is to write a loop with a sleep inside it. Use Ruby's Find class to locate the files that are candidates for processing. The Find documentation has example code to get that part started.
I was wondering if the following is possible.
I have a BASH script that I want to make available for some people but I wanted them to only have to "install" the program and not messing around with terminal, so I thought a .deb would be cool.
So what would the "install" do?
Simple. I want to move the script and an icon to a folder (any folder, but I was wondering some hidden folder in Home) and then run a script that creates a launcher in the Applications menu for the first script. It seems there isn't much to it, but for what I've searched, there doesn't seem to be a lot of info...
How can I accomplish this?
By the way, I'm using Ubuntu 11.04.
Basically (install and) run dh-make to set up the debian/ directory, edit the generated files (mainly remove the many you do not need, and fill in a package description and any dependencies in debian/control), then debuild-us -uc -b.
You may also have to set up a simple Makefile for debian/rules to call; it probably only needs an install target to copy the binary to $(DESTDIR)/usr/bin.
Binaries install into /usr/bin and you should not try to override that. The way to have a menu is to add a .desktop file.
Once you have a good .deb you will need to set up a repo for distributing it. The simplest solution is probably to set up a launchpad.net account and create a personal PPA there.
It's not hard to find more information on these topics, but of course, you need to know what to look for. The canonical documentation is the Debian New Maintainer's Guide.
Found this video on youtube that explains IN FULL the process of creating a *.deb for a script or program and even mentions how to do it for a C program.
Full guide in how to build simple *.deb package
Has one bug, btw, that the author, during the making of the *.deb, didn't notice. The path in the *.desktop file for the EXEC parameter is wrong in the example.
I'm building a large .NET project using Rake . We committed the Ruby environment to our source control and install gems to this "local" environment (like Albacore, Nokogiri, etc). We're essentially following this guidance, using the RubyInstaller for Windows zip package.
trunk/
source/
packages/
ruby/ <-- ruby here!
build.bat <-- helper scripts (call Ruby/rake)
Solution.sln
However, our source control server is remotely hosted, on a virtual machine, and the link speed is slow. I've read that some people have trimmed down the Ruby environment, like in the Machine.Specifications project. But, that looks extreme! (is there even gem support there?)
I could just start deleting files and directories to see what works, but there must be some known set of files that can be removed and still support basic Ruby, Rake, and gems?
From my own experimentation and investigation, it's kind of hard to determine what's "required" and what's optional. There are some files that appear very safe and easy to remove and others that I'd rather not play with. My results below only save about 5 MB... probably not enough to warrant doing this at all.
bin
The ruby/bin directory contains many batch scripts that are simply helpers to invoke the ruby executable with the correct "applicaton", like Rake or Gem. For example, rake.bat contains this line
#"%~dp0ruby.exe" "%~dpn0" %*
You can replace this with the right comamnd in your build.bat script (assuming it's "up" one level above the ruby environment, probably at the solution root)
#"%~dp0ruby\bin\ruby.exe" "%~dp0ruby\bin\rake" %*
You could dump the rest of the batch scripts, but then you'll have a little more trouble installing gems into the local environment.
cmd> ruby\bin\ruby.exe ruby\bin\gem install <whatever>
And, as of Ruby 1.9.3, that's only saving you 1.38KB. I'm sure some of those other non-extension files in this directory can be removed, but, without knowing what they do, it's unsafe to proceed.
include (175 KB)
The ruby/include directory appears to contain only C header files for developing against Ruby (I'm winging it here). I removed it and everything ran fine.
lib/tcltk (4.7 MB)
The ruby/lib/tcltk looks a lot like the include directory, but for Tcl programming.
lib/ruby
The ruby/lib/ruby directory contains the gems for this installation and a whole lot more scary stuff. I'd stay out of this directory unless you want to inadvertently cripple your environment.
share (27 KB)
The ruby/share directory appears to contain only help pages, dump 'em!
I have scripts that use #!/usr/bin/env ruby but I've switched to using Ruby Enterprise Edition instead of the default ruby that is included with Ubuntu server. Thus, the scripts freak out when I try to run them. How can I add the Ruby EE path to /usr/bin/env?
#!/usr/bin/env ruby is similar to simply calling ruby from the command line, so the same rules apply. Basically, the individual entries in the $PATH environment variable are checked in order, and the ruby that is found first is used. So make sure that the ruby for Ruby EE is earlier in the search path order than your other rubys.
I'm not familiar with Ruby EE, so if it doesn't have an executable called ruby, just create a symlink in a directory that's early in your search path to Ruby EE's executable.
Since you have an explicit dependency on Ruby EE, you could always modify the scripts instead of your environment ( which could have other unintended consequences ).
#!/usr/bin/env ruby
becomes
#!/path/to/enterprise/edition/ruby
Now it becomes clear to the reader that you using a specific version of ruby rather than just whatever ruby is in your path.
I had a similar problem where cron jobs stopped working... Cron seems to run commands by default without using the PATH settings you would expect for the user (when logging in as that user). In fact it didn't even seem to use any of the default PATH settings (be it in /etc/profile or elsewhere).
I was able to find the problem using the following commands (the first one is how cron seems to run commands):
su -c 'printenv PATH' userX
With output: /usr/local/bin:/usr/bin:/bin:/usr/games
su -l userX -c 'printenv PATH'
With output: /opt/ruby-enterprise-1.8.7-2010.02/bin/:/opt/ruby-enterprise-1.8.7-2010.02/bin/:/usr/local/bin:/usr/bin:/bin:/usr/games
The first command doesn't seem to populate the PATH variable in any way except for the bare system default.
In my case I solved it by just adding the necessary (REE) path to: /etc/login.defs, which by default looks as follows:
/etc/login.defs:103:ENV_PATH PATH=/usr/local/bin:/usr/bin:/bin:/usr/games
See section 1.6 in the Ruby EE documentation page:
http://www.rubyenterpriseedition.com/documentation.html
For a system wide change you can update your PATH in the /etc/environment file to include the Ruby EE bin directory. Maybe something like this:
PATH="/opt/ruby-enterprise-x.x.x/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games"
If you only want to the change to be visible for one user on the system you can update your .bashrc or .profile with the correct path.
Make sure to include the REE path first in the list of directories.
I posted the solution I used on Ubuntu here:
http://groups.google.com/group/emm-ruby/browse_thread/thread/d0c685bbd096823a#msg_effa7d6ad42c541c
There were some additional steps to get it working beyond what was described in the Ruby Enterprise Edition documentation.