How to programmatically read Mac .textClipping files?

Question

Those files are created whenever you drag a text selection to the Finder. The file size is always 0 bytes. Apparently the data is stored in a resource fork.

I tried reading the resource fork[1], but get error code -39 (end of file).

Here some more details about the file:

$>xattr  test.textClipping 
com.apple.FinderInfo
com.apple.ResourceFork

[1] http://www.cocoadev.com/index.pl?UsingResourceForks

Answer 1

A textClipping file is an old fashioned resource fork file. You'll want to open it using FSOpenResourceFile, and then use Get1Resource to read the resources out of the file. The file might contain a few different resources types for the text: 'RTF ' (rich text), 'utxt' (UTF-8), 'utf8' (UTF-8), or 'TEXT' (ASCII) type resources, all with id 256. Once you read the resource, extract the data from the Handle and do with it what you want.

Answer 2

It looks like in macOS 10.12 Sierra, a .textClipping file is now a property list.

The root dictionary has the key "UTI-Data". Within that, the keys: com.apple.traditional-mac-plain-text, public.utf16-plain-text, and public.utf8-plain-text hold a couple different representations of the data.

Here's an example that will read from a path:

NSString *path = @"/path/to/file.textClipping";
NSData *data = [NSData dataWithContentsOfFile:path];
id plist = [NSPropertyListSerialization propertyListWithData:data options:0 format:nil error:&error];
NSString *text;

if (plist && error == nil) {
  NSDictionary *utiData = [plist objectForKey:@"UTI-Data"];
  text = [utiData objectForKey:@"public.utf8-plain-text"];
}