Are there any characters (or character sequences) that are guaranteed not to be included in the metadata fields output by listformat? For example, angle brackets, ampersands, or something that's guaranteed to be escaped?

I'd like to use something as a separator, so that it can be easily machine-parsed, like that shown below. However, if there's any chance the separator could appear within a field, it could mess up the parsing.

Pipe symbol should be fine. That's why it is used in the cache files.

Thank you both, that's really helpful. I'll use the pipe then.

@GeoffSmith, you're almost certainly right, it could well be easier to work with the cache, but for historical reasons I'm using the output of a search command and I'd need to properly understand the characteristics of the cache before switching to using that instead (a task for another day).