http://www.pbs.org/parents/education/music-arts/the-benefits... (not my favorite source, but there are plenty of pointers to this data out there)
Few, because when tasked with a problem that this could solve, most people would immediately throw up their hands and give up. This is the biggest obstacle of all.
"Which pictures are you missing?" "I don't know, I'm not going to flip through them all!"
(This happens more often than I'd like to admit)
But what about a slightly different one? E.g.
I have two folders, each a bunch of files. Are there any files that are not in both folders?
edit: I did not know this- I just posted it because it is but one answer. For what it is worth, I agree with you- basic knowledge of programming is something everyone should know.
A lot of my coworkers.
They take a screenshot, thus offloading the hard part onto everyone who needs to get data out of their email.
It's about as awesome as it sounds.
At one point, the general mgr of our office, said that these things were so valuable to everyone, and I was so good at it and seemed to enjoy it so much, that he was wondering if it wouldn't make more sense for him to take me off of my own consulting cases and make IT projects my only case. Of course, IT people were thought of as lowly support staff for the elite consultants, so it would mean a pay cut and end my consulting career. This wasn't a warning; he was just thinking that this might better serve the needs of the firm.
That day I stopped being a valuable IT resource for my coworkers and reserved my dev skills for my giving myself a "sustainable competitive advantage" in my own work on my own cases.
The powerpoint extensions I used in consulting were created by ex-consultants so it's not unheard of to do this.
As far as the hard part goes, I'd think an OCR script could handle this even if they're using Comic Sans for their file manager font.
And yeah, that's an option that I've considered it in the past, but never been able to validate it because it'd take me less time to just transcribe it (or I can find a glob pattern from their screenshot, etc.).
You may not have the specific chops to write a program to do it, but you know that doing something to (x) files is just a loop with a if thingy inside of it.
I think part of the "learn to code" movement is also hope that currently non-tech-literate people will learn to help themselves. Once you've googled "how do I do this in python" and found answers enough times, you (hopefully) gradually replace "All of this computer stuff is confusing! I need someone to help me with it. My cousin is good with computers. I'll call him." with "I got this shit. What up, google."
It's about practice, not "knowledge" per se. Basic tasks, like: I have a folder full of files, how do I get the filenames into a text file or e-mail? Five-liners in high-level languages, the equivalent of asking for directions in a foreign tongue.
Of course, that idea comes from a time when one would own a universal computer, and own one's own data. You can argue that for many people, the filenames and text files I'm talking about are already a thing of the past, that it's all pinch and swipe, plus cloud storage.