linux - Setting umask for all users

I'm trying to set the default umask to 002 for all users including root on my CentOS box.

According to this and other answers, this can be achieved by editing /etc/profile. However the comments at the top of that file say:

It's NOT a good idea to change this file unless you know what you
are doing. It's much better to create a custom.sh shell script in
/etc/profile.d/ to make custom changes to your environment, as this
will prevent the need for merging in future updates.

So I went ahead and created the following file:
/etc/profile.d/myapp.sh
with the single line:

umask 002

Now, when I create a file logged in as root, the file is born with 664 permissions, the way I had hoped. But files created by my Apache mod_wsgi application, or files created with sudo, still default to 644 permissions...

$ touch newfile (as root):
Result = 664 (Works)

$ sudo touch newfile:
Result = 644 (Doesn't work)

Files created by Apache mod_wsgi app:
Result = 644 (Doesn't work)

Files created by Python's RotatingFileHandler:
Result = 644 (Doesn't work)

Why is this happening, and how can I ensure 664 file permissions system wide, no matter what creates the file?

Answer

profile is a startup file for the shell. Setting umask 002 in profile.d sets it for all users who start their processes from a login shell.

Your two examples are of a different nature. For Apache you might set the umask in the init.d script that starts the http server.

For processes started with sudo you could use the umask option in the sudoers file.