Can R cause a file to be opened by another program? - r

This is a bit of a strange question, but I thought people here might be interested.
Is it possible to have R cause a file to be opened in another program? For example, could you write a command line that would cause a music file to start playing? The potential application would be that after a model is finished running, music would start to play, alerting you to the model's completion.

In addition to system, on Windows at least you can use shell.exec which will open the file using the application specified in the Windows file associations. For example, shell.exec("file.txt") will open a text file in your favourite text editor, shell.exec("file.mp3") will launch a media player, etc.

There is audio package which allow to play wave files:
require(audio)
wave_file <- dir("C:/Windows/Media", pattern="\\.wav$", full.names=TRUE)[1] # some random windows wave file
f <- load.wave(wave_file)
play(f)

You can do this by calling the system() function.

Related

Programmatically access files in a device showing up in 'This PC'

I am on Windows 10. I want to write a function (in R) to copy the files stored in a camera (actually in the SD of the camera, but I cannot just read the memory card in the PC), to a different storage unit (say, the pc or an external HDD).
The camera is connected to the PC via an USB cable.
The problem I am facing is that, when opening the File Explorer, the camera is showing up as a link under "This PC" with no letter to indicate the drive (e.g., 'G:/').
While I can see the files using the file explorer window, I cannot find a way to get to those file from a cli type of interface (e.g., the command prompt, or the R console).
Googling, I found that 'This PC' is not a folder but rather a link to something in the registry called CLSID for which the identifier should be {20D04FE0-3AEA-1069-A2D8-08002B30309D}. However this is very confusing to me and I cannot figure out how to use this information.
Is there a way to do it? And if so: how?
Please consider I do not know much of commands from prompt (way better off in R).
A CLSID is just a GUID. My computer is a implementation of IShellFolder.
My Computer is part of the shell namespace. Several entries in the shell namespace are virtual (Control panel, scheduled tasks etc.) and cannot be accessed with low-level file functions nor cmd.exe.
While it would be possible to develop a tool that does something like shellcopy Computer\MyCamera\*.jpg x:\backup, I'm not aware of any existing tools that do this. You might have to code it yourself.
In the old days you would call SHGetDesktopFolder to get the root and then use the returned IShellFolder to navigate but these days it is simpler to use IShellItem instead.
To do this it is crucial to understand how IShellFolder and PIDLs work. See Introduction to the Shell Namespace for more information...

Raspberry Pi Custom SD Card Image

I have a project uses Qt GUI which works on raspberry-pi2; however I don't want users to interact with the operating system. I just want that the only application appears on the screen (from boot to shutdown) to be is my application. Actually the retropie project has done what I actually want. So I want to prepare an minimal SD Card image like that. Is there any tool or way to do that?
You can use openembedded http://www.openembedded.org/wiki/Main_Page for this.
Creat file that describe packages for your image, at your case base system + qt,
plus create description of package of your program, that include .service file for run you program at start with systemd. The command MACHINE=raspberry-something bitbake your-image
I'd just use the init scripts to run your application as soon as possible and make it handle all user inputs (keyboard and mouse) properly, without giving any way to the user to close it.

RStudio R File Corruption

I had a R script open in RStudio. The file was saved many times over the course of several weeks and worked perfectly fine when RStudio was opened and closed. However, today, I restarted my computer and when I opened RStudio and more specifically the script that I mentioned, all of the R code vanished, leaving a single long row of "....." with red highlighting.
When I tried to open the R file in other text processors such as Sublime Text and Notepad++, only a line of zeroes was visible. None of my other R files were affected. I'm currently running Windows 8.1 and have the latest version of R and RStudio. What can I do to recover the code in the file and prevent something like this from happening again?
It might be an old thread and it might have been covered in 'user4458796' answer in suggestion #1 ("Use the history..."), but:
My friend had the same problem and we managed to recover the code from a 'history_database' files located on Windows at:
'C:\Users\%user%\AppData\Local\RStudio-Desktop\'
I assume there is an equivalent location in Linux in general.
Hopefully I won't get downvoted, just sharing my 2cents.
Ben.
It's not clear what happened to corrupt your file (and thus how to fix it if possible) and it is kind of ominous that you're just seeing 0's in other text editors, but I'll give you my best suggestion and some tips.
Suggestions for Attempting Recovery
Since your other R files were unaffected, you should have a messy record of your code in the history. Use the history to reconstruct your code.
Access a copy of your file from any version control, cloud, or offline backup you may have used -- git, SVN, iCloud, SugarSync, Dropbox, etc (I realize you probably wouldn't have posted this question if that were an option, but I had to throw it out there).
Use a Hex or sector editor to try to recover the data.
Use a data recover program to find an old version of your file.
Inspect your trash or recycling bin to see if it has an old version. Depending on your OS and the settings of how you (insecurely or securely) delete files, then you may be able to undelete a deleted version, even if it's not immediately available.
Try different methods of recovering text data from corrupted text files like OpenOffice's and Microsoft's suggestions.
Tips for the Future
I know that hindsight is 20/20, but a few quick tips for good measure:
Use version control. Git is supported in RStudio's GUI interface.
Have more than one version of your file. Many professors and professionals recommend writing/storing code in a text editor and using your IDE only for the working copy.
Make backups. Distinct from #2, you should backup your files to a hard drive, flash drive, or cloud service like Dropbox or Spideroak.

Visual Studio 2012: run executable (or addon) on save

so I've just begun using Visual Studio 2012 as a new programmer, and I'd like to find a way to have VS2012 automatically save (or at least automatically convert) files to UNIX line endings.
I found this page as a means of creating an executable that could be integrated with VS2010 as a macro. Since VS2012 no longer uses macros, how can I set this up so that this is executed on my files at save? I don't want to have to go to Advanced Save everytime I save a file (I tend to save every 30 seconds or so out of paranoia).
I began trying to construct an add in to handle this for me, but as a beginner I'm afraid that's a bit beyond me.
Thank you in advance for the help.
you can do like this,
click File, choose Save .... as, then in the save file dialog, choose save with Encoding, another dialog shows up, you can choose Unix format.

Run BAT file from Adobe AIR?

To package an .air file into a native installer you have to use a batch program called adt.
The command on Windows will look something like this:
C:\Users\jisaacks>"C:\Program Files
(x86)\Adobe\Adobe Flash Builder
4\sdks\4.1.0\bin\adt" -package -target
native "D:\DEV\Flex4\Workspaces\AIR
Native Packager\AIRNIP\AIRNIP.exe"
"D:\DEV\Flex4\Workspaces\AIR Native
Packager\AIRNIP\AIRNIP.air"
I am trying to author a program in AIR that does this for you. Basically you drag/drop an .air file into it and it packages it into a native installer.
Well It gave me an Error #3219 error, which I looked up and found this:
AIR on Windows does not allow you to
run .bat files directly. Windows .bat
files are executed by the command
interpreter application (cmd.exe).
When you invoke a .bat file, this
command application can interpret
arguments passed to the command as
additional applications to launch. A
malicious injection of extra
characters in the argument string
could cause cmd.exe to execute a
harmful or insecure application. For
example, without proper data
validation, your AIR application may
call myBat.bat myArguments
c:/evil.exe. The command application
would launch the evil.exe application
in addition to running your batch
file.
If you call the start() method with a
.bat file, the NativeProcess object
throws an exception. The message
property of the Error object contains
the string "Error #3219: The
NativeProcess could not be started."
I am wondering if there is a possible work around or if I have hit a brick wall?
I believe you have hit a brick wall, at least with trying to do this in Adobe Air. Executing batch files can be a huge security hole, as your post claimed.
Are you trying to do this in Air for portability, or would you be able to use some other language?
I suggest trying to code this in python. Using the subprocesslibrary can help a lot.
http://docs.python.org/release/2.5.2/lib/module-subprocess.html
Serge Jespers (Adobe Evangelist) (http://www.webkitchen.be/) has done exactly this,
I think you should try to contact him for the details.
I helped him build a first solution by creating a windows executable which executed any bat file you specified, later he changed it by calling the java application (adt) directly which works fine as well.
He'll be very happy to help you.
UPDATE:
You can download the Package Assitant Pro right here: http://www.webkitchen.be/package-assistant-pro/

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