Try add an extra parameter `shell=True` to the `Popen` call. 

Just a note. `shell=True` was likely the correct solution to the o.p., since they did not make the following mistake, but you can also get the &quot;No such file or directory&quot; error if you do not split up your executable from its arguments.

    import subprocess as sp, shlex
    sp.Popen([&#39;echo 1&#39;]) # FAILS with &quot;No such file or directory&quot;
    sp.Popen([&#39;echo&#39;, &#39;1&#39;]) # SUCCEEDS
    sp.Popen([&#39;echo 1&#39;], shell=True) # SUCCEEDS, but extra overhead
    sp.Popen(shlex.split(&#39;echo 1&#39;)) # SUCCEEDS, equivalent to #2

Without `shell=True`, Popen expects the executable to be the first element of args, which is why it fails, there is no &quot;echo 1&quot; executable. Adding `shell=True` invokes your system shell and passes the first element of `args` to the shell. i.e. for linux, `Popen([&#39;echo 1&#39;], shell=True)` is equivalent to `Popen(&#39;/bin/sh&#39;, &#39;-c&#39;, &#39;echo 1&#39;)` which is more overhead than you may need. See [Popen() documentation][1] for cases when `shell=True` is actually useful.


  [1]: https://docs.python.org/2/library/subprocess.html#popen-constructor

You have to give the full path to your program `deactivate` and then it the subprocess module should be able to find it.

I&#39;m spawning subprocesses like that:

    SHUTDOWN_CMD = os.path.sep.join([&quot;c:&quot;, &quot;windows&quot;, &quot;system32&quot;, &quot;shutdown.exe&quot;])
    
    def abortShutdown():
        os.spawnv(os.P_NOWAIT, SHUTDOWN_CMD,
            [SHUTDOWN_CMD, &#39;/A&#39;])
        time.sleep(3)

I&#39;m not using subprocess since Python 2.5 does not support it. I had to use use the FULL path to have it working and I guess you also have to use the full path to your custom commands.

Arrays have a &quot;length&quot; property by default.

Can I add custom properties to them?

Without having to make them objects.




Add a property to a JavaScript array

Since yesterday, I&#39;ve been facing a compiling error for my C project. The project itself consists on creating a service that will make some tasks.

I don&#39;t what has changed since yesterday, but this morning, my code can&#39;t compile anymore.

Here are the errors I have :

    c:\path\main.c(56): error C2275: &#39;SERVICE_TABLE_ENTRY&#39; : illegal use of this type as an expression
    c:\program files\microsoft sdks\windows\v7.0a\include\winsvc.h(773) : see declaration of &#39;SERVICE_TABLE_ENTRY&#39;
    c:\path\main.c(56): error C2146: syntax error : missing &#39;;&#39; before identifier &#39;DispatchTable&#39;
    c:\path\main.c(56): error C2065: &#39;DispatchTable&#39; : undeclared identifier
    c:\path\main.c(56): error C2059: syntax error : &#39;]&#39;
    c:\path\main.c(57): error C2065: &#39;DispatchTable&#39; : undeclared identifier
    c:\path\main.c(57): warning C4047: &#39;function&#39; : &#39;const SERVICE_TABLE_ENTRYA *&#39; differs in levels of indirection from &#39;int&#39;
    c:\path\main.c(57): warning C4024: &#39;StartServiceCtrlDispatcherA&#39; : different types for formal and actual parameter 1

Here&#39;s the code concerned by these errors (from lines 45 to 58) :

    int main(int ac, char *av[])
    {
    	if (ac &gt; 1)
    	{
            if (!parse_args(ac, av))
    	    {
    		aff_error(ARGUMENTS);
    		return EXIT_FAILURE;
    	    }
    	}
    	SERVICE_TABLE_ENTRY DispatchTable[] = {{MY_SERVICE_NAME, ServiceMain}, {NULL, NULL}};
    	StartServiceCtrlDispatcher(DispatchTable);
    	return EXIT_SUCCESS;
    }

And here&#39;s the code of my ServiceMain function :

    void WINAPI ServiceMain(DWORD ac, LPTSTR *av)
    {
    	gl_ServiceStatus.dwServiceType = SERVICE_WIN32;
    	gl_ServiceStatus.dwCurrentState = SERVICE_START_PENDING;
    	gl_ServiceStatus.dwControlsAccepted = SERVICE_ACCEPT_STOP;
    	gl_ServiceStatus.dwWin32ExitCode = 0;
    	gl_ServiceStatus.dwServiceSpecificExitCode = 0;
    	gl_ServiceStatus.dwCheckPoint = 0;
    	gl_ServiceStatus.dwWaitHint = 0;
    	gl_ServiceStatusHandle = RegisterServiceCtrlHandler(MY_SERVICE_NAME, ServiceCtrlHandler);
    	if (gl_ServiceStatusHandle == (SERVICE_STATUS_HANDLE)0)
    		return;
    	gl_ServiceStatus.dwCurrentState = SERVICE_RUNNING;
    	gl_ServiceStatus.dwCheckPoint = 0;
    	gl_ServiceStatus.dwWaitHint = 0;
    	SetServiceStatus(gl_ServiceStatusHandle, &amp;gl_ServiceStatus);
    }

I couldn&#39;t manage to find some answers that fit my problem, could anyone helps ? Thanks !

error C2275 : illegal use of this type as an expression

I have some custom commands.

    # works 
    subprocess.Popen([&#39;python&#39;], stdout=subprocess.PIPE)

But if I have my own system commands like `deactivate`, I get that error

    Traceback (most recent call last):
      File &quot;runner2.py&quot;, line 21, in &lt;module&gt;
        main() 
      File &quot;runner2.py&quot;, line 18, in main
        subprocess.Popen([&#39;deactivate&#39;,], stdout=subprocess.PIPE)
      File &quot;/usr/lib/python2.6/subprocess.py&quot;, line 633, in __init__
        errread, errwrite)
      File &quot;/usr/lib/python2.6/subprocess.py&quot;, line 1139, in _execute_child
        raise child_exception
    OSError: [Errno 2] No such file or directory

Let alone I need to execute this under my sandbox virtualenv. 




Popen error: [Errno 2] No such file or directory

I have some custom commands.
<pre><code class="hljs language-ini"># works 
subprocess.Popen(['python'], stdout=subprocess.PIPE)
</code></pre>
But if I have my own system commands like <code>deactivate</code>, I get that error
<pre><code class="hljs language-arduino">Traceback (most recent call last):
 File "runner2.py", line 21, in &#x3C;module>
 main() 
 File "runner2.py", line 18, in main
 subprocess.Popen(['deactivate',], stdout=subprocess.PIPE)
 File "/usr/lib/python2.6/subprocess.py", line 633, in __init__
 errread, errwrite)
 File "/usr/lib/python2.6/subprocess.py", line 1139, in _execute_child
 raise child_exception
OSError: [Errno 2] No such file or directory
</code></pre>
Let alone I need to execute this under my sandbox virtualenv.

I always read that I should use

    model = Model(a=5, b=6)
    model.save()

But I just saw there is a manager function create, because I saw an opensource django app using it.

    model = Model.objects.create(a=5, b=6)
    print model.pk
    1

So is it suggested to use it? Or is it still preferred to use the .save method. I&#39;m guessing that objects.create will try to create it no matter what, whereas save may save an existing object if the pk is specified.

These are the docs that I found: https://docs.djangoproject.com/en/dev/topics/db/queries/#creating-objects

Django model manager objects.create where is the documentation?

I&#39;m having problems dealing with unicode characters from text fetched from different web pages (on different sites). I am using BeautifulSoup. 

The problem is that the error is not always reproducible; it sometimes works with some pages, and sometimes, it barfs by throwing a `UnicodeEncodeError`. I have tried just about everything I can think of, and yet I have not found anything that works consistently without throwing some kind of Unicode-related error.

One of the sections of code that is causing problems is shown below:

    agent_telno = agent.find(&#39;div&#39;, &#39;agent_contact_number&#39;)
    agent_telno = &#39;&#39; if agent_telno is None else agent_telno.contents[0]
    p.agent_info = str(agent_contact + &#39; &#39; + agent_telno).strip()


Here is a stack trace produced on SOME strings when the snippet above is run:

    Traceback (most recent call last):
      File &quot;foobar.py&quot;, line 792, in &lt;module&gt;
        p.agent_info = str(agent_contact + &#39; &#39; + agent_telno).strip()
    UnicodeEncodeError: &#39;ascii&#39; codec can&#39;t encode character u&#39;\xa0&#39; in position 20: ordinal not in range(128)


I suspect that this is because some pages (or more specifically, pages from some of the sites) may be encoded, whilst others may be unencoded. All the sites are based in the UK and provide data meant for UK consumption - so there are no issues relating to internalization or dealing with text written in anything other than English.

Does anyone have any ideas as to how to solve this so that I can CONSISTENTLY fix this problem?



UnicodeEncodeError: &#39;ascii&#39; codec can&#39;t encode character u&#39;\xa0&#39; in position 20: ordinal not in range(128)

I want to do a string replace in Python, but only do the first instance going from right to left. In an ideal world I&#39;d have:

    myStr = &quot;mississippi&quot;
    print myStr.rreplace(&quot;iss&quot;,&quot;XXX&quot;,1)
    
    &gt; missXXXippi

What&#39;s the best way of doing this, given that `rreplace` doesn&#39;t exist?

Right-to-left string replace in Python?

I know it&#39;s an  easy way of doing it but i didn&#39;t find it neither here nor on google. 
So i was curious if there is a way to install multiple packages using pip. 
Something like: 

    pip install progra1 , progra2 ,progra3 ,progra4 . 

or:

    pip install (command to read some txt containing the name of the modules) 

How to install multiple python packages at once using pip 

I was wondering what the use of the comma was when slicing Python arrays - I have an example that appears to work, but the line that looks weird to me is

    p = 20*numpy.log10(numpy.abs(numpy.fft.rfft(data[:2048, 0])))

Now, I know that when slicing an array, the first number is start, the next is end, and the last is step, but what does the comma after the end number designate? Thanks.

Python Array Slice With Comma?

    import os

    import subprocess

    proc = subprocess.Popen([&#39;ls&#39;,&#39;*.bc&#39;], stdout=subprocess.PIPE, stderr=subprocess.PIPE)

    out,err = proc.communicate()

    print out


This script should print all the files with .bc suffix however it returns an empty list. If I do ls *.bc manually in the command line it works. Doing [&#39;ls&#39;,&#39;test.bc&#39;] inside the script works as well but for some reason the star symbol doesnt work.. Any ideas ?



subprocess wildcard usage

I have a small issue that I&#39;m not quite sure how to solve. Here is a minimal example:

### What I have

    scan_process = subprocess.Popen(command, stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
    while(some_criterium):
        line = scan_process.stdout.readline()
        some_criterium = do_something(line)

### What I would like

    scan_process = subprocess.Popen(command, stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
    while(some_criterium):
        line = scan_process.stdout.readline()
        if nothing_happens_after_10s:
            break
        else:
            some_criterium = do_something(line)

I read a line from a subprocess and do something with it. How can I exit if no line arrived after a fixed time interval?






Timeout on subprocess readline in Python

I&#39;m using eSpeak on Ubuntu and have a Python 2.7 script that prints and speaks a message:

    import subprocess
    text = &#39;Hello World.&#39;
    print text
    subprocess.call([&#39;espeak&#39;, text])

eSpeak produces the desired sounds, but clutters the shell with some errors (ALSA lib..., no socket connect) so i cannot easily read what was printed earlier. Exit code is 0. 

Unfortunately there is no documented option to turn off its verbosity, so I&#39;m looking for a way to only visually silence it and keep the open shell clean for further interaction.

How can I do this?

How to hide output of subprocess

Since `os.popen` is being replaced by `subprocess.popen`, I was wondering how would I convert

    os.popen(&#39;swfdump /tmp/filename.swf/ -d&#39;)

to `subprocess.popen()`

I tried:

    subprocess.Popen(&quot;swfdump /tmp/filename.swf -d&quot;)
    subprocess.Popen(&quot;swfdump %s -d&quot; % (filename))  # NOTE: filename is a variable
                                                    # containing /tmp/filename.swf

But I guess I&#39;m not properly writing this out. Any help would be appreciated. Thanks

How to use subprocess popen Python

I&#39;m trying to write a small script to mount a VirtualBox shared folder each time I execute the script. I want to do it with Python, because I&#39;m trying to learn it for scripting.

The problem is that I need privileges to launch mount command. I could run the script as sudo, but I prefer it to make sudo by its own.

I already know that it is not safe to write your password into a .py file, but we are talking about a virtual machine that is not critical at all: I just want to click the .py script and get it working.

This is my attempt:

    #!/usr/bin/env python
    import subprocess
             
    sudoPassword = &#39;mypass&#39;
    command = &#39;mount -t vboxsf myfolder /home/myuser/myfolder&#39;

    subprocess.Popen(&#39;sudo -S&#39; , shell=True,stdout=subprocess.PIPE)
    subprocess.Popen(sudoPassword , shell=True,stdout=subprocess.PIPE)
    subprocess.Popen(command , shell=True,stdout=subprocess.PIPE)

My python version is 2.6

Using sudo with Python script

I&#39;m using the `subprocess.Popen` call, and in another question I found out that I had been misunderstanding how Python was generating arguments for the command line.  

**My Question**  
Is there a way to find out what the actual command line was?  

Example Code :-

    proc = subprocess.popen(....)
    print &quot;the commandline is %s&quot; % proc.getCommandLine()

How would you write `getCommandLine` ?

output the command line called by subprocess?

Can someone explain why the result I want, &quot;hi&quot;, is preceded with a letter &#39;b&#39; and followed with a newline?  

I am using **Python 3.3**

    &gt;&gt;&gt; import subprocess
    &gt;&gt;&gt; print(subprocess.Popen(&quot;echo hi&quot;, shell=True,
                               stdout=subprocess.PIPE).communicate()[0])
    b&#39;hi\n&#39;

This extra &#39;b&#39; does not appear if I run it with python 2.7

Why does Popen.communicate() return b&#39;hi\n&#39; instead of &#39;hi&#39;?

I am using Popen to call a shell script that is continuously writing its stdout and stderr to a log file. Is there any way to simultaneously output the log file continuously (to the screen), or alternatively, make the shell script write to both the log file and stdout at the same time?  

I basically want to do something like this in Python:

    cat file 2&gt;&amp;1 | tee -a logfile #&quot;cat file&quot; will be replaced with some script

Again, this pipes stderr/stdout together to tee, which writes it both to stdout and my logfile. 

I know how to write stdout and stderr to a logfile in Python. Where I&#39;m stuck is how to duplicate these back to the screen:

    subprocess.Popen(&quot;cat file&quot;, shell=True, stdout=logfile, stderr=logfile)

Of course, I could just do something like this, but is there any way to do this without tee and shell file descriptor redirection?:

    subprocess.Popen(&quot;cat file 2&gt;&amp;1 | tee -a logfile&quot;, shell=True)



Content Type	Original Author	Original Content on Stackoverflow
Question	user1012451	View Question on Stackoverflow
Solution 1 - Python	Anthony Kong	View Answer on Stackoverflow
Solution 2 - Python	Mark Woodward	View Answer on Stackoverflow
Solution 3 - Python	Senthil Kumaran	View Answer on Stackoverflow
Solution 4 - Python	katzenversteher	View Answer on Stackoverflow

Popen error: [Errno 2] No such file or directory

Python Problem Overview

Python Solutions

Solution 1 - Python

Solution 2 - Python

Solution 3 - Python

Solution 4 - Python

error C2275 : illegal use of this type as an expression

Add a property to a JavaScript array

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