I have been researching this problem for two days, and I know there are many other posts about it. But the solutions are always "fix the permissions". That does not solve it for me. I have recursively changed the permissions on the symbolic and original directory trees to 777 and I still get the error. Not only is the PID file not being updated, but the error file is not being written either, though the error message in Terminal when I try to start MySQL says that it is. That does suggest something is preventing processes from writing to the directory, but it's not file permissions.
Here's the full error message:
Starting MySQL .Logging to '/usr/local/mysql/data/Sheryls-MacBook-Pro.local.err'. /usr/local/mysql/bin/mysqld_safe: line 198: 11197 Trace/BPT trap: 5 nohup /usr/local/mysql/bin/mysqld --basedir=/usr/local/mysql --datadir=/usr/local/mysql/data --plugin-dir=/usr/local/mysql/lib/plugin --user=mysql --log-error=Sheryls-MacBook-Pro.local.err --pid-file=/usr/local/mysql/data/Sheryls-MacBook-Pro.local.pid < /dev/null > /dev/null 2>&1 ERROR! The server quit without updating PID file (/usr/local/mysql/data/Sheryls-MacBook-Pro.local.pid).
Also, here are my permissions, so you can see this is not the problem:
Sheryls-MacBook-Pro:mysql Sheryl$ ls -laF
total 48
drwxrwxrwx 13 root wheel 442 Apr 13 14:48 ./
drwxr-xr-x 9 root wheel 306 Apr 13 14:48 ../
-rwxrwxrwx 1 root wheel 17987 Dec 27 22:46 COPYING*
-rwxrwxrwx 1 root wheel 2478 Dec 27 22:46 README*
drwxrwxrwx 40 root wheel 1360 Jan 24 08:41 bin/
drwxrwxrwx 6 _mysql _mysql 204 Apr 13 14:48 data/
drwxrwxrwx 5 root wheel 170 Jan 24 08:41 docs/
drwxrwxrwx 50 root wheel 1700 Jan 24 08:41 include/
drwxrwxrwx 2 _mysql _mysql 68 Apr 13 14:48 keyring/
drwxrwxrwx 11 root wheel 374 Apr 13 14:48 lib/
drwxrwxrwx 4 root wheel 136 Jan 24 08:41 man/
drwxrwxrwx 39 root wheel 1326 Jan 24 08:41 share/
drwxrwxrwx 6 root wheel 204 Jan 24 08:41 support-files/
I'm running MacOS 10.11.6 (El Capitan). Apache is enabled and working, and PHP is enabled and working. Both are the versions that came pre-installed. MySQL is v5.7.21. I've removed and reinstalled it 3 times now. This version does not come with a configuration file.
Should I try an older version of MySQL??
Does anyone have an answer to this problem?