What is the location of mysql client ".my.cnf" in XAMPP for Windows?

After checking the default locations on Win7 with mysql --help and unable to find any config file, I manually searched for my.ini and found it at C:\ProgramData\MySQL\MySQL Server x.y (yep, ProgramData, not Program Files).

Though I used an own my.ini at Program Files, the other configuration overwrote my settings.

Look in the MySQL config file C:\xampp\mysql\bin\my.ini.

At the top of that file are some comments:

# You can copy this file to
# C:/xampp/mysql/bin/my.cnf to set global options,
# mysql-data-dir/my.cnf to set server-specific options (in this
# installation this directory is C:/xampp/mysql/data) or
# ~/.my.cnf to set user-specific options.

There it tells you where to find your .my.cnf file.

Type this:

mysql --help 

Then look at the output. There is a block of text about 3/4 the way down describing what files it finds its defaults .my.cnf from. Here is an example from XAMPP v3.2.1, default options are read from the following files in the given order:

C:\Windows\my.ini 
C:\Windows\my.cnf 
C:\my.ini 
C:\my.cnf 
C:\xampp\mysql\my.ini 
C:\xampp\mysql\my.cnf 
C:\xampp\mysql\bin\my.ini 
C:\xampp\mysql\bin\my.cnf

Your setup may differ. You will have to run the command to check the actual paths on your particular system.