After doing some research it is supposed to be under ~/Library/Application Support/Bitcoin/
But on my computer there is no Bitcoin.conf under ~/Library/Application Support/Bitcoin !
So where do I find Bitcoin.conf?
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Sign up to join this communityBitcoin.conf usually arent come with it so you have to make one manually by making a file and naming it bitcoin.conf
After you made it, you can use the link below to use the configuration as template
Hope the answer above is what your looking for
by default it goes into the path that you described. If the path was changed, then a search in finder can help. However: search in finder doesn't look into every directory. Try to search for filenames "wallet.dat" or "mempool.dat". Also press the left ALT key, and chose "go to", and select library. Then again do the search in finder. Only then my location was found with the mentioned files. If this doesn't help, open a terminal, and try this:
cd /Users
find . -type f -name wallet.dat
there might be many Permission denied messages, but it would show, if file was found. If not, there is simply no message. If this still doesn't help, go another directory up ("cd /"), and try again. Time to search will massivly increase then...
Running the Bitcoin core software the first time should create that directory, but then that also loads the mainnet as default. If you don't want that, then you must first manually create the directory and then the Bitcoin.conf file before running the software
i.e
mkdir $HOME/Library/Application\ Support/Bitcoin
vi $HOME/Library/Application\ Support/Bitcoin/Bitcoin.conf
Next proceed to open the file and set
testnet=1
Now run the bitcoin core software to see its now reading from testnet