Use cmd commands in QT - qt

Hi i was checking and anyone can use commands very similar in cmd like dir mkdir etc.
But for example when i try to use command (cd ..) i couldn't
QProcess consola;
consola.start("cmd.exe /C " + comando);
consola.waitForFinished();
consola.waitForReadyRead();
This is the question how i can use more commands in cmd for qt for example.

At least from the command line:
cmd /C "cd \"
works as did directories other than root. (Note the parenthesis around the command since it contains embedded spaces.) However, this example isn't very useful because this executes the command shell, changes the directory in that command shell, and then the command shell disappears, and your current directory is back to where you started.
I recommend looking into the QDir class, which has methods such as "current ()" and "setCurrent ()" for getting and setting the current directory. There are equivalents for mkdir and many others. Also, using QDir is much more cross-platform friendly, where using the "cmd" shell is Windows-specific.
You don't say what you're trying to accomplish, so beyond that suggestion, it's impossible to know how to best help you.

Your process's current directory can be and mostly is different than current directory of your is running. Please read chdir manpage for that.
That command is mostly working but changing the current directory of your process.

Related

Way to get jupyter server root directory

Consider following:
$ cd /home/mydir
$ jupyter notebook --port=8888
In plain English, I am running jupyter server from /home/mydir directory.
Is there a simple way to get this directory from within a notebook regardless if it's a R notebook or a Python notebook or whatever? Maybe there is some magic command or variable?
NOTE: getwd() is not an answer as it returns directory of a current notebook but not the jupyter server root.
I have a similar problem and found your post, although I don't see a viable solution yet. Eventually I did found a solution, although it works only because I only care about Linux and I only care about Python. The solution is this magic line:
J_ROOT = os.readlink('/proc/%s/cwd' % os.environ['JPY_PARENT_PID'])
(I put it in a module in my PYTHONPATH so that I can easily use it in any Python notebook.) See if it is good for you.
Remember that your iPtyhon is just a Python module, so you can execute any valid Python code in a cell. So, if you started your notebook and haven't executed any directory changes in your code, you should be able to retrieve your cwd with the following in a cell:
import os
os.getcwd()
But furthermore, you can execute shell commands in cells, so you can retrieve other information in the cell. For example:
!which jupyter
should give you the path to your jupyter executable.
Which then leads you to running something like:
!jupyter --paths
which should give you something similar to:
​
config:
/Users/yourdir/.jupyter
/usr/local/etc/jupyter
/etc/jupyter
data:
/Users/yourdir/Library/Jupyter
/usr/local/share/jupyter
/usr/share/jupyter
runtime:
/Users/yourdir/Library/Jupyter/runtime
Frankly I'm surprised that all this time later there is still no built-in way to do this. I have used Isaac To's solution on Linux but recently had to make a jupyter notebook portable to Windows as well. Simply using os.getcwd() is fragile because a cell using it to set your JUPYTER_ROOT_DIRECTORY can potentially be called again, after you have changed your working directory.
Here is what I came up with:
try:
JUPYTER_ROOT_DIRECTORY
except NameError:
JUPYTER_ROOT_DIRECTORY = os.getcwd()
I put it in one of the first couple cells with the initial import statements. If the cell gets called again, it will not re-set the variable value because the variable exists and does not throw an exception.
It should be noted that unlike Isaac To's solution it sets the value to the directory the current .ipynb was run from, which is not necessarily the same directory as the top-level dir the user can access in the left hand file pane.
My suggestion is to use an intuitive approach.
Create a new folder within the Jupyter environment with a very unique name, for example, T246813579.
You can now locate the Jupyter working path by searching in your file explorer. For example, you can use the Windows Explorer in order to locate your new folder.
The expected result should look something like this:
C:\Users\my_user_name\JupyterHome\T246813579
The answer from #Isaac works well for Linux, but not all systems have /proc. For a solution that works on macOS and Linux, we can use shell commands, taking advantage of the ! shell assignment syntax in Jupyter:
import os
JPY_ROOT = ! lsof -a -p {os.environ['JPY_PARENT_PID']} -d cwd -F n | tail -1 | cut -c 2-
JPY_ROOT = JPY_ROOT[0]
print(JPY_ROOT) # prints Jupyter's dir
Explanation:
Get the process ID (pid) of the current jupyter instance with os.environ['JPY_PARENT_PID']
Call lsof to list the process's open files, keeping only the current working dir (cwd)
Parse the output of lsof using tail and cut to keep just the directory name we want
The ! command returns a list, here having only one element
Alternate Version
To save the os import, we could also use shell commands to get the PID. We could also do the subsequent string wrangling in python, rather than calling tail and cut from the shell, as:
JPY_ROOT = ! lsof -a -p $(printenv | grep JPY_PARENT_PID | cut -d '=' -f 2) -d cwd -F n
JPY_ROOT = JPY_ROOT[2][1:]

Multiple shell commands in Windows

I'm trying to replicate a shell command in R and cannot figure out how to string commands together. This just returns the contents of the working folder (system() fails for some reason):
> shell("dir")
Volume info ..
Directory of E:\Documents\R
contents are listed..
Now lets try and navigate to C drive and run dir (without using the obvious dir C:)..
> shell("cd C:")
C:\
> shell("dir")
Volume in drive E is GT
etc..
So it seems commands can't be entered separately as the shell doesn't remember the working directory. So..
> (cmd = "cd C:
+ dir")
[1] "cd C:\ndir"
> shell(cmd)
C:\
No luck as the C: folders are not reported. Other methods I've tried also fail. Grateful for any ideas.
The documentation explains why system doesn’t work: it executes the command directly on Windows, without spawning a shell first.
shell (or better, system2) is the way to go but as you’ve noticed, shell will always spawn a new shell so that changes to the environment don’t carry over. system2 won’t work directly either since it quotes its commands (and thus doesn’t allow chaining of commands).
The correct solution in this context is not to use a shell command to change the directory. Use setwd instead:
setwd('C:')
system2('dir')
If you want to reset the working directory after executing the command, use the following:
local({
oldwd = getwd()
on.exit(setwd(oldwd))
setwd('C:')
system2('dir')
})
I'm on Linux and this works for me:
system("cd ..;ls")
in navigating to the previous directory and running ls/dir there. In your case, on Windows, this apparently works:
shell("cd C: & dir")
or to get the output as a character vector:
shell("cd C: & dir", intern=T) and on Linux: system("cd ..; ls", intern=T)
Don't know if this helps, but collapsing the commands to one string when using system works on MacOS
cmds <- c("ls", "cd ..", "ls");
system(paste(cmds, collapse=";"))
This is a solution from here. That solved my problem in calling the windows dir command:
system("cmd.exe /c dir", intern=TRUE)

run a "source" bash shell script in qmake

I want to use the intel compiler for Qt, but using the intel compiler implies running the script
$ source /opt/intel/bin/compilervars.sh intel64
Of course, I could add this to ~/.bashrc, but this would not run it in QtCreator, where it still complains about missing icpc. So I want it to be a part of the main mkspec qmake file.
How can I execute that full bash command in qmake?
Short Answer: Using QMAKE_EXTRA_TARGETS and PRE_TARGET_DEPS, you can execute source /opt/intel/bin/compilersvars.sh intel64, but simply sourcing them will not solve your issue.
Long Answer: The QMake file is converted into a Makefile. Make then executes the Makefile. The problem you will run into is that Make executes each command in its own shell. Thus, simply sourcing the script will only affect one command, the command that executes the script.
There are a couple of possible ways to make things work:
Execute the script before starting Qt-Creator. I've actually done this for some projects where I needed to have special environment variables setup. To make my life easier, I created a shell command to setup the environment and then launch Qt-Creator.
Within Qt-Creator, modify the Build Environment for the project I've also used this trick. In your case, simply look at the environment setup by the script and change the "Build Environment" settings under the project tab for your project to match those setup by the script.
It might also be possible to modify QMake's compiler commands, but I am not sure you can make it execute two commands instead of one (source the script then execute the compiler). Further more, this will make the project very un-transportable to other systems.
You can create a shell script that does more or less the following:
#! /usr/bin/env sh
# Remove the script's path from the PATH variable to avoid recursive calls
SCRIPT_DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
export PATH=${PATH/$SCRIPT_DIR:/}
# Set the environment up
source /opt/intel/bin/compilervars.sh intel64
# Call make with the given arguments
make "$#"
Save it into a file named "make" in an empty directory somewhere, make it executable, then change the build environment in QT Creator to prepend PATH with the script's directory:
PATH=[dir-of-make-script]:${Env:PATH}
You can do this either in the project settings or once and for all in the kit settings.
Like this, QT Creator will be fooled into calling your make script which sets up your environment before calling the actual make binary. I use a similar technique under Windows with Linux cross-toolchains and it has been working well so far.

How to run a R language(.r) file using Batch file?

I want to run a R script file (.r) using batch file.
If R.exe is in your PATH, then your windows batch file (.bat) would simply consist of one line:
R CMD BATCH your_r_script.R
otherwise, you need to give the path of R.exe, so for example:
"C:\Program Files\R\R-2.13.0\bin\R.exe" CMD BATCH your_r_script.R
you can add certain input arguments to the BATCH command, such as --no-save, --no-restore
so it would be
R CMD BATCH [options] your_r_script.R
more info on options, etc at http://stat.ethz.ch/R-manual/R-devel/library/utils/html/BATCH.html
Note: R uses the command "BATCH" to non-interactively evaluate a script located in a file. Here we are running the command "BATCH" from a windows .BAT file, but that's merely a coincidence.
An answer to another question suggests using Rscript.exe, so your batch file would contain:
"C:\Program Files\R\R-3.0.2\bin\i386\Rscript.exe" your_script.R
pause
It is a good idea to add R to the windows environment path. In a comment in this question #chase gave a link that explains how to set the path on windows 7. Once R is added to the windows path, your batch file should become simply :
Rscript.exe your_script.R
pause
You can also directly call a R command by using the -e flag. For example this batchfile will tell R to set its current working directory to Documents, then it will print the working directory:
Rscript.exe -e setwd('Documents');getwd()
pause
I struggled with the syntax with the answers below, but this worked for me in the .bat file:
C:\Windows\System32\cmd.exe /k ""path to Rscript.exe"
"path to .R script""
Be sure to place both the path to Rscript.exe and the script in "" together and separately as above.
I doubt you will be able to run it using a batch file.
http://www.fileinfo.com/extension/r
Most known programs that use .r files do so for source code files it looks like. You will probably have to compile it using the program it was written for. I guess you could use a command line compiler from a batch file, but I don't know what language or applications you are using.
If you post the script file or give more information about it, we could probably help you better.

"exec source <script>" does not work in tcl

I'm trying to call a script in Tcl with the command:
exec source <script path>
and I get the error
couldn't execute "source": no such file or directory
How can I call another script from tcl?
Edit: I am running a command I got from another person in my office. I was instructed to run "source " explicitly with source. So in other words, how would I run any command that would work in cshell, in Tcl?
If the script you were given is a cshell script, you can exec it like this:
exec /bin/csh $path_to_script
In effect, this is what the 'source' command does from within an interactive shell. It's not clear whether this is really what you want to do or not (not exactly, but close enough for this discussion).
The reason you can't exec the source command is that exec will only work on executable files (hence the name 'exec'). The source command isn't implemented as an exectuable file, it is a command built-in to the shell. Thus, it can't be exec'd.
If you really feel the need to exec the source command or any other built-in command you can do something like this:
exec /bin/csh -c "source $path_to_script"
In the above example you are execing the c shell, and asking it to run the command "source ". For the specific case of the source command, this doesn't really make much sense.
However, I'm not sure any of this will really do what you expect. Usually if someone says "here's some commands, just do 'source ', it usually just defines some aliases and whatnot to be used from within an interactive shell. Those aliases won't work from within Tcl.
source in csh, like . in bash, executes a script without spawning a new process.
The effect is that any variable that is set in that script is available in current csh session.
Actually, source is a built-in command of csh, thus not available from tcl exec, and using exec without source would not give the specific source effect.
There is no simple way to solve your problem.
source load the source file
you should do:
source <script path>
If you want to execute it, then you need to call the main proc.
another option would be to do:
exec [info nameofexecutable] <scritp path>
Some confusion here. exec runs a separate program, possibly with arguments.
source is not a separate program, it is another Tcl command which reads a file of Tcl commands and executes them, but does not pass arguments. If the other script you are trying to call is written to be run on from the command line, it will expect to find its arguments as a list in variable argv. You can fake this by setting argv to the list of arguments before running source, eg.
set argv {first_arg second_arg}
source script_path
Alternatively you could use exec to start a whole separate Tcl executable and pass it the script and arguments:
exec script_path first_arg second_arg
the error speaks for itself. Make sure you give the correct path name, specify full path if necessary. and make sure there is indeed the file exists in that directory
Recently I wanted to set some UNIX environment variables by sourcing a shell script and stumbled across the same problem. I found this simple solution that works perfectly for me:
Just use a little 3-line wrapper script that executes the source command in a UNIX shell before your Tcl script is started.
Example:
#!/bin/csh
source SetMyEnvironment.csh
tclsh MyScript.tcl

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