Better way to parse a config File in C++ [closed] - c++

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I am currently working on a parser project to get some file xml format 1 to another xml format.
I finished my project, and there is quiet a lot of parameters to know, most of them are paths to some files, lists of parameters, ...
I would like it to be easy to use so I create a settings.txt : it contains lines like
someparameter = defaultvalue
This file is easy to modify.I consider case where people want to parse files with same parameters, so my application is like :
Do you want to change parameters? (Y/N)
if(yes){
Do you want to change paramater 1? //If no value, [] stays
[pathbydefault]
}
...
else{ load from settings.txt}
To implement this, I use getline(), splitting on first '=' and put them in a std::map.
I think this is a bad choice, I searched and I found a lot of architecture for c++: list (really heavy for 10 parameters), table (not easy to read, the code is dark for other people).
What solution would you advise me to use?
Of course, i dont ask for implementation, just for some solution to consider.
Some info: I dont think if it matters a lot, but I work on Unix based system (Mac OS or Linux) so I cant use windows libraries. I saw a windows solution but I did not go further into this.

Answer 1

The rule of thumb with this stuff (IMHO) is to always use a good library to parse a standard data format, at least in any situation where your needs might continue to scale. For example, I tend to really be fond of JSON because it's a simple, easy to humanly read/write format, with quite a few good quality choices in C++.
This avoids having to deal with any bug prone parsing logic yourself. It also makes it very easy to e.g. write python scripts that generate or verify your configuration files (since python has very easy access to json as well, as about every language does).
In your code it may also be a good idea to cleanly separate the data format, and the collection into a map or whatever data structure you're using. That way, the portion of the code that will change if you decide to change which data format you use is contained.

Answer 2

One future consideration would be using XML transformation language to transition between an old XML file format and a new XML file format. I'm not sure if you're already doing this or not, so if you are, please disregard. If you're unfamiliar, the most common of these languages is XSLT (eXtensible Stylesheet Language Transformations).
Rather than having the end-user enter a myriad of options/paths/values to an INI-styled configuration file, the end-user would ideally only supply XML (which can easily be edited by hand) / XSLT template files to the XSLT processor. You could update your C++ application to focus less on obtaining every input from the end-user and more on creating/choosing the right XML/XSLT template files.
As you mention working on Unix-based systems, you might want to consider this processor: http://xml.apache.org/xalan-c/