get 'Documents' path in Matlab - matlab

Question

I understand you can probably use the following code to get the job done in most cases:
mydocpath = fullfile(getenv('USERPROFILE'), 'Documents');
However, if the user has moved 'Doucments' folder to a different location, for example: E:\Documents, the above code won't work, since getenv('USERPROFILE') always returns C:\Users\MY_USER_NAME.
In C#, one can use Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments), which always returns the correct path regardless where 'Documents' is. Is there anything similar in Matlab?
My current solution is rather clumsy and probably unsafe:
% search in the MATLAB path lists
% this method assumes that there is always a path containing \Documents\MATLAB registered already
searchPtn = '\Documents\MATLAB';
pathList = strsplit(path,';');
strIdx = strfind(pathList, searchPtn);
candidateIdx = strIdx{find(cellfun(#isempty,strIdx)==0, 1)}(1);
myDocPath = pathList{candidateIdx}(1 : strIdx{candidateIdx}+ numel(searchPtn));

Answer 1

Based on #excaza 's suggestion, I came up with a solution using dos and the cmd command found here to query the registry.
% query the registry
[~,res]=dos('reg query "HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\User Shell Folders" /v Personal');
% parse result
res = strsplit(res, ' ');
myDocPath = strtrim(res{numel(res)});
Edit:
If the document folder in customer's PC has not been relocated or moved to one of the environment path such as %SYSTEMROOT%, the above method would return
%SOME_ENVIRONMENT_PATH%/Documents(Or a custom folder name)
The above path will not work in Matlab's functions such as mkdir or exist, which will take %SOME_ENVIRONMENT_PATH% as a folder name. Therefore we need to check for the existence of environment path in the return value and get the correct path:
[startidx, endidx] = regexp(myDocPath,'%[A-Z]+%');
if ~isempty(startidx)
myDocPath = fullfile(getenv(myDocPath(startidx(1)+1:endidx(1)-1)), myDocPath(endidx(1)+1:end));
end
Full code:
% query the registry
[~,res]=dos('reg query "HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\User Shell Folders" /v Personal');
% parse result
res = strsplit(res, ' ');
% get path
myDocPath = strtrim(res{numel(res)});
% if it returns %AAAAA%/xxxx, meaning the Documents folder is
% in some environment path.
[startidx, endidx] = regexp(myDocPath,'%[A-Z]+%');
if ~isempty(startidx)
myDocPath = fullfile(getenv(myDocPath(startidx(1)+1:endidx(1)-1)), myDocPath(endidx(1)+1:end));
end