How must (Not how can) a program be available from everywhere in CentOS/Fedora

Question

I was reading this link from MySQL: https://dev.mysql.com/doc/refman/5.6/en/mysql-cluster-install-linux-binary.html

shell> cp support-files/mysql.server /etc/rc.d/init.d/
shell> chmod +x /etc/rc.d/init.d/mysql.server
shell> chkconfig --add mysql.server

In the mysql.server file the content says:

PATH=$PATH:/usr/local/SomeDir/mysql/bin
export PATH

But checking the $PATH variable the /usr/local/SomeDir/mysql/bin was not added.

Now, I was looking for the proper solution of this.

I found these links:

• https://stackoverflow.com/questions/10235125/linux-custom-executable-globally-available

  Edit your .bashrc to add the desired directory on the PATH environmental variable.
      export PATH=/usr/local/google_app_engine/bin:$PATH
  then, either start new terminal or do,
      source ~/.bashrc
  Now try to run the script from anywhere.
  

• How can I make a program executable from everywhere

  If you just export PATH=$PATH:. at the command line it will only last for the length of the session though.
  If you want to change it permanently add export PATH=$PATH:. to your ~/.bashrc file (just at the end is fine).
  

• https://rajesh9333.wordpress.com/2013/09/12/mysql-binary-installation-on-linux-redhat-and-centos-servers/

  Create a file with the name of mysql.sh at the path /etc/profile.d/
  # vi /etc/profile.d/mysql.sh
      #!/bin/sh
      PATH=$PATH:/usr/local/mysql/bin
      export PATH
  

• http://sgdba.blogspot.com/2013/08/install-mysql-56-binary-on-centos-64-64.html

  [root@CentOS ~]# echo "export PATH=$PATH:/usr/local/mysql/bin" >>/etc/profile
  [root@CentOS ~]# source /etc/profile
  

Question

In CentOS 6.x what is the proper place (path or location) to put this file with instruction?

Comment: Maybe before solutions works, my question is, how MUST put my instructions. My question is about styles...

Thank you

Answer 1

First part of this question refers to some how to, which is NOT making program available from everywhere -- it is making the program available from that particular init script, which is the correct solution for such task.

Second part lists the correct solution to make it available from everywhere. If you see manual pages for bash(1), you can see the difference in description:

/etc/profile
    The systemwide initialization file, executed for login shells
~/.bashrc
    The individual per-interactive-shell startup file

So the difference is

• when the file is loaded: shell startup OR login
• if it is available for the specific user OR for all users

The difference profile.d version is only that you write it in other file, but I think you can make up that it has the same meaning as putting it into /etc/profile.