If it a feral adult cat it's probably beyond being domesticated.
@PeterS Not true. I have a formally feral female cat laying next to me on a stool. She was one of the feral cats I feed behind a store,and I fed her from the time she was a kitten,to the time she was maybe 2 or 3 years old before bringing her home.
I was feeding the cats one day when she came up to me and started rubbing her head against my ankles and purring. I had never even touched her before,but I just picked her up,put her in my truck,and took her home with me. It wasn't long before I figured out what her plan was. She was pregnant,and there were problems with the pregnancy. I took her to the vet and she had 9 kittens with the help of surgery,but all buy 1 died. I brought that one home and tried to bottle feed him until his mother was well and could nurse,but he only lasted 3 days. She is still in my house 3 years later,and damned if she isn't half again as big as she was now that she can eat her fill and sleep without having to run away from other animals.
I also have 4 other cats I got from behind those dumpsters. The big tom was a yellow stripped kitten someone dropped off with his sister just before a big snow storm maybe 3 years ago. His sister froze to death one night,and he was sick and going blind. Luckily for him,there was a little tom there at the time that seemed to "adopt and babysit" sick kittens,and that's how I figured out the yellow tom kitten was sick and going blind. He couldn't get far away from where he was fed because he was weak and couldn't see very good,so the other little tom stayed with him and hugged him to keep him warm. I just picked him up one day and took him to the vet. We managed to save one eye,but the other had to be taken out. The most recent is a little crazy female that was really too young to be weaned when she was dropped off,and just about starved by the time I caught her. She is as nice as she can be one day,and the next day walk around with her back humped and spitting at anything that moves.
Somebody dropped off some kittens there a week ago. The guy that feeds them in the morning caught one,but there is a really fuzzy black one I spotted a few days ago that ran away and hasn't been seen since,and a couple of days ago I spotted a tiny little fluff ball Maine Coon looking kitten. She is so tiny she hops instead of running. She actually started to come right up to me tonight when I fed them,but there was a new adult black shorthair female there that hisses and scared her away. This was a housecat somebody dropped off. I know this because when she saw me coming with the food bag,she ran right up to me to get fed,and she was so hungry she got under the bag when I was pouring the food out and tried to eat is as it was falling. Any adult cat that will walk right up to a stranger in the open is a house cat. Plus her fur was bright and shiny. When she hissed,the kitten shrieked,spun around,and hopped away,and that got all of them running.
I suspect I will be catching that adult female in the next few days and talking her to the SPCA. Going to try to catch the kittens and take them there,too.