psql on Mac

Hi,

I am behind a Mac, and I have been trying to get a local server running by
following an internet tutorial (which also uses Mac, this one<
https://video.cs50.net/web/2018/spring/lectures/>).

I simply try to run psql on the terminal, and I get various error messages,
depending on how I mess up the file "pg_hba.conf", for example by adding
the following lines to it, among others:

local postgres postgres trust
local all postgres trust

I have spent the whole morning browsing the internet to find a solution to
my problem, and I also tried backtracking from version 11 of PostgreSQL to
version 10. I am pasting below some of the error messages that I get. The
version 10 warns for no support for Mac; is that the problem?

Perhaps, it is me who hasn't been able to dig out the right information
from the internet. However, I must say that I am quite surprised that
things get so tedious immediately. I will thus be glad if you could help me
with getting this running, perhaps by providing some up-to-date
documentation.

Thanks,
Ozan

XX:src3 ozan$ psql

Password:

sql: FATAL: password authentication failed for user "ozan"

XX:src3 ozan$ psql

Password:

psql: FATAL: password authentication failed for user "ozan"

XX:src3 ozan$ sudo -u postgres psql

Password:

Sorry, try again.

Password:

sudo: 1 incorrect password attempt

XX:src3 ozan$ sudo -u postgres psql

Password:

Sorry, try again.

Password:

could not identify current directory: Permission denied

Password:

could not identify current directory: Permission denied

psql: could not find own program executable

XX:src3 ozan$ sudo -u postgres psql

could not identify current directory: Permission denied

Password:

could not identify current directory: Permission denied

psql: could not find own program executable

XX:src3 ozan$ psql

Password:

=========================================
Ozan Kahramanoğulları, PhD
http://sites.google.com/site/ozankahramanogullari/
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University of Trento, Department of Mathematics
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