BenCello

I am writing an external (in C/C++) which is able to save and load (text based) files. I followed the SDK instruction to write the save and load functions so I can give my external either the file name alone or a full path/filename combination. And it works well.

However, I would like to have an additional feature: I would like my object to create the directory given in the full path/filename combination if it doesn't exist yet. For example if I give my external the message 

write System:/Users/Me/Desktop/Name/File.json

 and the folder "Name" doesn't exist on my desktop, I would like it to create the folder then write the file inside.

I would be ok with a solution which creates the folder outside of my external, prior to sending the write message to my object. But I have read this post about it 

https://cycling74.com/forums/create-directory

 and it doesn't seems to be any way without Java or a custom external. As I am writing my own external too, I'd rather integrate this feature to it than depend on someone else's code.

Do you have any idea which function(s) I could use in the API to do it ?

However, I would like to have an additional feature: I would like my object to create the directory given in the full path/filename combination if it doesn't exist yet. For example if I give my external the message write System:/Users/Me/Desktop/Name/File.json and the folder "Name" doesn't exist on my desktop, I would like it to create the folder then write the file inside.

I would be ok with a solution which creates the folder outside of my external, prior to sending the write message to my object. But I have read this post about it https://cycling74.com/forums/create-directory and it doesn't seems to be any way without Java or a custom external. As I am writing my own external too, I'd rather integrate this feature to it than depend on someone else's code.

create-directory-2

Take a look at this code to get an idea of how to do it:

https://github.com/jamoma/JamomaModular/blob/master/implementations/MaxMSP/jcom.folder/jcom.folder.cpp

Take a look at this code to get an idea of how to do it:
https://github.com/jamoma/JamomaModular/blob/master/implementations/MaxMSP/jcom.folder/jcom.folder.cpp

I'll have a look and try to find my way around...

Thank's Timothy
I'll have a look and try to find my way around...

Thank's to you code Timothy, I think I have the behavior I wanted...

if (s == gensym(""))
        {      // if no argument supplied, ask for file
            if (saveasdialog_extended(filename, &newpath, &outtype, &filetype, numtypes))     // non-zero: user cancelled
                return;
        }
        else
        {
            strcpy(fullpath, s->s_name);
            path_frompotentialpathname(fullpath, &path, filename);
            foldername = strrchr(fullpath, '/');
            if (foldername)
            {
                *foldername = 0;
                foldername = strrchr(fullpath, '/');
                if (foldername)
                {
                    *foldername = 0;
                    foldername++;
                    err = path_frompathname(fullpath, &path, temp);
                    if (!err)
                        err = path_createfolder(path, foldername, &newpath);
                    if (err)
                        object_error((t_object*)x, "error creating folder", err);
                }
                else
                    path_frompathname(fullpath, &newpath, temp);
            }
            else
            {
                newpath = path_getdefault();
                strcpy(filename, s->s_name);
            }
        }

PS: I have an afterthought, maybe the behavior I wanted isn't obvious. Here is a bit more information :

I wanted it to be consistent with the usual "write" message which creates a file wherever you say if you give an argument and asks for a place if you don't. Except that I wanted it to be able to create the last folder if it doesn't exists. And only the last one (to avoid mistakes).

Thank's to you code Timothy, I think I have the behavior I wanted...
Here is my code :

if (s == gensym(""))
		{      // if no argument supplied, ask for file
			if (saveasdialog_extended(filename, &newpath, &outtype, &filetype, numtypes))     // non-zero: user cancelled
				return;
		}
		else
		{
			strcpy(fullpath, s->s_name);
			path_frompotentialpathname(fullpath, &path, filename);
			foldername = strrchr(fullpath, '/');
			if (foldername)
			{
				*foldername = 0;
				foldername = strrchr(fullpath, '/');
				if (foldername)
				{
					*foldername = 0;
					foldername++;
					err = path_frompathname(fullpath, &path, temp);
					if (!err)
						err = path_createfolder(path, foldername, &newpath);
					if (err)
						object_error((t_object*)x, "error creating folder", err);
				}
				else
					path_frompathname(fullpath, &newpath, temp);
			}
			else
			{
				newpath = path_getdefault();
				strcpy(filename, s->s_name);
			}
		}

PS: I have an afterthought, maybe the behavior I wanted isn't obvious. Here is a bit more information :
I wanted it to be consistent with the usual "write" message which creates a file wherever you say if you give an argument and asks for a place if you don't. Except that I wanted it to be able to create the last folder if it doesn't exists. And only the last one (to avoid mistakes).


Probably a bit of an aside, but it's pretty easy (in the Mac world at least, and I assume in the Windows world) to lift your utility code into C++ and just use the standard C++ libraries for portable file I/O. You'll just have to call into the MaxAPI for things like Max path interrogation and conversion between different filename formats.

create directory