File names with spaces used as command line arguments

I am trying to run an external program with command line arguments. The syntax is like this:

bertini <inputFile> <startpointFile>

The problem is, if one of the files in the command line has a space in its name, I can't get it to work. For example, if commandStr = 'bertini paramotopy.input /Users/my folder/start', then

[status,result] = system(str)

returns an error because bertini thinks the startpoint file is /Users/my.

I have not been able to make any of the usual suggestions involving backslashes or double quotes work for this example. I need it to work for both Windows and Unix-based systems.

Comment added: Bertini is not a Matlab executable; it is an entirely separate product that was written in C. Unfortunately, I don't have the option of altering its code. Sorry for the misunderstanding - it didn't occur to me that people would assume this.

Answer 1

[Image Analyst]

Try this, where I was trying to accept a foldername, that contained images, via the command line of a compiled executable:

if isdeployed && ~isempty(varargin)
  % For some reason, it won't take the command line as a single item, even if it's in double quotes.
  % It splits it up and gets rid of leading and trailing spaces so that
  % "D:\word1 word2\theUser\Images"
  % becomes 2 cells:
  % varargin{1} = "D:\word1 
  % varargin{2} = word2\theUser\Images"
  % We need to join all these together.
  numberOfCells = length(varargin);
  if numberOfCells >= 1
    commandLineArgument = varargin{1};
    for k = 2 : numberOfCells
      thisWord = varargin{k};
%         fprintf(1, 'varargin{%d} = %s\n', k, thisWord);
      commandLineArgument = sprintf('%s %s', commandLineArgument, thisWord);
    end
    % Get rid of any quotes.
    commandLineArgument = strrep(commandLineArgument, '"', []);
    fprintf(1, 'The argument passed in on the command line is %s\n', commandLineArgument);
%       msgboxw(['The argument passed in on the command line is ', commandLineArgument]);
    if exist(commandLineArgument, 'dir')
      % If this folder exists, use it.
      handles.imageFolder = commandLineArgument;
      fprintf(1, 'Changed image folder to this: %s\n', handles.imageFolder);
    else
      fprintf(1, 'This folder does not exist, so we cannot change to it:\n     %s\n', commandLineArgument);
    end
  end
  fprintf(1, 'handles.imageFolder = %s\n', handles.imageFolder);
end

[Andrew Newell]

Thanks to everyone for their suggestions. It appears that the issue is with how Bertini interprets command line arguments, so I have re-designed my program to get around that. Image Analyst, I'm accepting your answer because it might be useful to someone who is creating a stand-alone program using MATLAB.

Answer 2

[Robert Cumming]

try putting " around the command,

commandStr = '"bertini paramotopy.input /Users/my folder/start"'

edit

So the problem is running the bertin code - I would first try to get that working on its own from the command line the way you want it to (it might not be possible...) then transfer that methodology into the system command.

The input parser for your c code is space delimited - so it will be interpreting your 2 commands as 3 (since the 2nd has a space in it...).

[Andrew Newell]

Nope. That is one of the usual suggestions that I mentioned. It works fine if I am trying to run a command like

/Users/my folder/bertini

but not for the command line arguments.

[Robert Cumming]

ah sorry misunderstood. try single quotes or can you pass a file in. Ultimately this is an issue with bertini api and not really matlab

Answer 3

[Sean de Wolski]

Perhaps try the ! operator:

!bertini paramotopy.input /Users/my folder/start

[Andrew Newell]

No difference, I'm afraid.

[Image Analyst]

Did you try what I showed you? Assuming "bertini" is the MATLAB-code executable that you compiled into a standalone executable, and are trying to pass in arguments for, I know for a fact that this will work. I've been through what you're going through and basically I had to "rebuild" the command line from the parts. I know it works because I use it in my systems all the time.

Answer 4

[per isakson]

This should work at least on Windows

    commandStr = 'bertini paramotopy.input "/Users/my folder/start"';
    [status,result] = system( commandStr );

if not what does result say?

[Image Analyst]

It's been a while but I'm pretty sure that doesn't work when passed in to a MATLAB executable. Andrew and I both tried that. That's why he's asking - note he said he tried double quotes. And that's why I did the method I showed.

[per isakson]

• "when passed in to a MATLAB executable" &nbsp Is the problem with "compiled" Matlab code? I assumed it was interpreted mode.
• the problem might be special to bertini
• I usually use absolute paths

[Image Analyst]

I assumed that "MATLAB executable" means that he compiled his m-file, bertini.m, into a standalone executable. In that case he will observe the situation that he and I both did. However his latest edit indicates it's not a MATLAB executable but some other program. In that case, it's up to the other program to handle it properly, which it does not.

In my code I also use absolute paths. If you try to pass an absolute path into a MATLAB executable, with spaces in it, in as a command line argument you will have a problem. Say another program launches your MATLAB executable, and wants to feed it some folder on the command line. The executable will interpret it as multiple arguments regardless if it's enclosed in single or double quotes or just bare. Again, we learned that it's not his situation anymore.

[per isakson]

I would try

    bertini paramotopy.input "/Users/my folder/start"

at Windows Command Prompt (the DOS window).

[Image Analyst]

Good suggestion. If it fails, then we know it has nothing to do with MATLAB and it's all bertini's fault.