identification

I was thinking along the lines of using typeid() but I don't know how to ask if that type is a subclass of another class (which, by the way, is abstract) You really shouldn't. If your program needs to know what class an object is, that usually indicates a design flaw. See if you can get the behavior you want using virtual functions. Also, more information about what you are trying to do would help. I am assuming you have a situation like this: class Base; class A : public Base {...}; class B : public Base {...}; void foo(Base *p) { if(/* p is A */) /* do X */ else /* do Y */ } If this is what

I am currently using PIL. from PIL import Image try: im=Image.open(filename) # do stuff except IOError: # filename not an image file However, while this sufficiently covers most cases, some image files like, xcf, svg and psd are not being detected. Psd files throws an OverflowError exception. Is there someway I could include them as well? A lot of times the first couple chars will be a magic number for various file formats. You could check for this in addition to your exception checking above. I have just found the builtin imghdr module. From python documentation: The imghdr module determines

I have a folder full of files and these doesn't have an extension. How can I check file types? I want to check the file type and change the filename accordingly. Let's assume a function filetype(x) returns file type like png . I want to do this: files = os.listdir(".") for f in files: os.rename(f, f+filetype(f)) How do I do this? There are Python libraries that can recognize files based on their content (usually a header / magic number) and that don't rely on the file name or extension. If you're addressing many different file types, you can use python-magic . That's just a Python binding for