I have installed some command line clients using pip that should run straight from the command line without the python keyword and using the path to the file.
For instance shub from scrapinghub or turbolift
All I get is:
shub: command not found
and
turbolift: command not found
What environment variables should I add to .bash_profile to enable the desired command line behaviour?
The directory which contains the script you want to run must be added to your PATH.
For example, to add $HOME/bin/pip/, you would use
PATH=$HOME/bin/pip:$PATH
to add it at the front. (If it's not frequently used, and doesn't need to override system commands, maybe add to the end instead.)
Many guidelines add export PATH but this is normally unnecessary, as the system startup files will already have declared this particular variable to be exported.
This is an extremely basic and very frequently asked question.
Related
I am having difficulty accessing my custom scripts from the command line (python3 unzipit.py "C:\Users\Me\downloads\zipfilehome"). I want to have my scripts act on any file, no matter where they are. I don't want to have the script file in the same directory in order for it to work. I followed this question's top answer to no avail. Note: I am using Windows 10 and all my python versions are in the path with no issues accessing them.
What I did (I always refresh my CLI with every change)
In the system environmental variables:
Path: (unchanged since installation) C:\Path2Python27;C:\Path2Python27\scripts;C:\Path2Python37;C:\Path2Python37\scripts;
PYTHONPATH: C:\Path2Python37;C:\Path2Python37\scripts;C:\Users\Me\myscripts\py
Things I also tried
system environmental variables
Path: C:\Path2Python27;C:\Path2Python27\scripts;C:\Path2Python37;C:\Path2Python37\scripts;C:\Users\Me\myscripts\py
moving the same stuff to user env's Path
moving the above-shown system PYTHONPATH to the user env
What else am I missing? I don't understand.
All in all, what I needed to get this working:
system environmental variables
Path: C:\Path2Python27;C:\Path2Python27\scripts;C:\Path2Python37;C:\Path2Python37\scripts;
PYTHONPATH: C:\Users\Me\myscripts\py
and
making sure to use Andriy's comment. It won't work using python3 unzipit.py "C:\link\to\folder".
In order to achieve what you want you have to specify -m flag and the module name, so python will retrieve module by looking up python module path. See more here in interface-options. The command shall be:
python3 -m unzipit "C:\Users\Me\downloads\zipfilehome"
This is my directory structure
src\
dirCode\
dirSubCode\
test.py
Django\
DjangoApp\
Home\
views.py
From within views.py I'm trying to import a class (let's call it Main) from test.py. The line in test.py is simply
from dirCode.dirSubCode.test import Main
and I'm getting a ModuleNotFoundError when I try to run the server. I printed out the os.sys.path and the second entry points to 'src\' while the first entry is simply ''. Since this is not the only app from where I'm going to need to call "external" code I'm trying to avoid hard-coding
sys.path.insert(0,'path\to\src\dirCode\dirSubCode\')
if that would even work. I've tried looking through documentation, looking at other StackOverflow questions (Import module from subfolder), etc. but I'm at a loss as to how to do this. I've tried going into the src\Django\DjangoApp\Home directory and just running a python console and simply trying to import the class but it's giving me the same error.
One odd development that I'm running into is that when I try to run it from the Anaconda Prompt (yes, I'm running Windows) it doesn't work but when I run the file in PyCharm it does work. If that helps provide some insight as to what might be going on I'd appreciate the help.
The proper way to do this is to introduce a shared package that you can install into a virtualenv for each webapp. Either from an actual release, or by using
python setup.py develop
Form within the shared package you essentially create a symlink in the venv that allows you to just import.
A more modern and simpler version is
pip install -e .
inside the library. See Python setup.py develop vs install
I believe you need to set the PYTHONPATH variable, which is used to set the default search path for modules.
https://docs.python.org/2/using/cmdline.html#envvar-PYTHONPATH
As per the python docs the syntax is like so...
https://docs.python.org/3.6/using/windows.html#excursus-setting-environment-variables
To temporarily set environment variables, open Command Prompt and use the set command:
C:\>set PATH=C:\Program Files\Python 3.6;%PATH%
C:\>set PYTHONPATH=%PYTHONPATH%;C:\My_python_lib
C:\>python
Pycharm- in the Run/Debug configuration- sets it when you have it checked off (which is the default).
I have been looking into bash and shell recently and been trying to work out how git is able to make a terminal command that runs C scripts in the current directory e.g git init, git push/pull etc.
I have been trying to simulate it in python, by making an executable python script in my home directory,
#!/usr/bin/env python
import os
print("current_dir: ",os.getcwd()) #prints /Users/usr/folder/script.py
Then I create a .command file that calls the python script
cd
cd FOLDER/
python3 SCRIPT.py
and editing the bash profile to export a variable to run the .command file.
export mycommand=/Users/urn/folder/command.command
Although this is not even nearly close to the way git achieves its command line. For example, when I run my script is not actually a terminal command it is just an environment variable, hence the $.
$mycommand
Secondly, this goes to the directory of the python file and runs the script from with that directory, therefore the output will always be the same
/Users/usr/folder/script.py
Although in git it runs the file in the current directory. Therefore the print statement would change depending on the terminal directory.
How am I able to create my own 'terminal command' such as git init to run my python script in whatever directory I'm in. Ps, I'm on mac.
Any help would be greatly appreciated :)
It sounds like you are missing at least two basic concepts:
The search path: when you issue a command that is not a shell function or built-in and that has an unqualified name (one with no / characters), the shell searches a list of zero or more directories for a matching executable file. This list of directories is the "path", and it is stored in the PATH environment variable. You can change it if you wish. This is how the shell finds the git program when you do not specify a path to it.
Executable scripts: Python, shell, Perl, etc. programs that must be run via an interpreter can be made executable by name alone by including an appropriate shebang line as the very first line and assigning an executable mode. You include an appropriate shebang line in your example Python program, in fact, but you seem not to understand its significance, because you explicitly launch the script via the python3 command. The shebang line is just another comment to Python, but it is meaningful to the system.
It seems like you probably also are missing some other concepts, like the fact that your script doesn't need to be in the current working directory for you to run it via the python3 launcher, path notwithstanding. Just specify its full pathname. Alternatively, Python has its own variation on a path, PYTHONPATH, by which it can locate modules and packages. These are alternatives, however -- the first two points are enough to achieve your apparent objective. Specifically,
Keep the shebang line in your script, though your default python is probably v2.7, so if you really want to run it specifically via python3 then modify the shebang line to say so:
#!/usr/bin/env python3
Make sure the file has executable mode. For example,
chmod 0755 /Users/urn/bin/SCRIPT.py
Then you should be able to execute the script from anywhere via its full pathname.
To access it from anywhere via its simple name, ensure that the directory containing it is in your path. For this purpose, it would be wise to choose an appropriate directory, such as /usr/local/bin or /Users/urn/bin (you may need to create the directory first). Whichever you choose, ensure that that directory is in your PATH. For example, edit /Users/urn/.bash_profile, creating it if necessary, and ensure that it contains (say) the commands
PATH=$PATH:/Users/urn/bin
export PATH
That will take effect in new Terminal windows you open afterward, but not automatically in any that are already open. In those windows, you will be able to run the script, from anywhere, via its simple name.
I have installed gdal version 1.11.2, however I have problems with undefined symbols. A proposed solution for this is given by gerrit:
export LD_PRELOAD=/usr/local/lib/libgdal.so.1
However, this only works if I call the python script from the command line. If I call the script from a subprocess.Popen, this will obviously not work.
Is there a way to define the LD_PRELOAD permanently?
you can save the export in your /etc/environment if you want to have it globally for every user
or you can use the env argument like so:
subprocess.Popen(command, env={'LD_PRELOAD': '/usr/local/lib/libgdal.so.1'})
see also here:
Python subprocess/Popen with a modified environment
The best solution IMHO is to fix the problem at OS level. If you want gdalto be accessible to only some users of your platform, each user should add the line
export LD_PRELOAD=/usr/local/lib/libgdal.so.1
in his own .profile file (assuming they all use bash or a compatible shell)
Alternatively, if all users should be able to use gdal, that line should be added to the system /etc/profile file.
In Windows 8, I often use the Python Windows Launcher like
py C:/long/long/long/long/long/path/to/prog.py ...
Is there any way to set some environment setting, such as PATH or PYTHONPATH etc, to prevent having to type the full path to prog.py?
From my basic knowledge/research, PATH only helps with the py part of the command line and PYTHONPATH only helps with imports within prog.py, so how do I deal with the path to prog.py itself??
Notes:
I cannot modify the code, not even the "shebang" line, since it is needed to work on other platforms.
I cannot cd to the directory containing the programs to run them, because the programs will do something based on the directory they're run in (they'll modify the files in the directory they're run in).
I know that if I associate .py extension with the Python Windows Launcher, then I can run prog.py as the first item in the command line, and thus use PATH, but currently my .py extension is associated with my favorite editor and I'd like to keep it that way if possible (so I can double-click any Python file in Windows Explorer and edit it).
However, if someone suggests a solution where I can have a different association for Windows Explorer versus the command line, then that could be a potential solution! (i.e. in Windows Explorer, .py opens with the editor, while on command line, .py runs with Python Windows Launcher)
Add your long path to PYTHONPATH, then invoke your program as such:
python -m prog
Python will search for a module called prog and then run it as the main module.
Answer to my own question: Actually, I'm so silly. I could just set a variable for each program path (there are only a few programs paths), i.e.. prog=C:/long/path/to/prog.py and then do py %prog% .... I guess I figured out an answer to my own question that was acceptable to me.
Update: I just found something even better. I can do
doskey prog=py C:/long/path/to/prog.py $*
and then simply prog ... afterward
Now I just have to do some crazy stuff to get the doskey command into a file that will be run every time I start a console, as described here: https://stackoverflow.com/a/21040825/5182136