Mac updatedb to enable locate command

The first time to call locate command, one will get the message:

WARNING: The locate database (/var/db/locate.database) does not exist.

To create the database, run the following command:

  sudo launchctl load -w /System/Library/LaunchDaemons/com.apple.locate.plist

Please be aware that the database can take some time to generate; once

the database has been created, this message will no longer appear.

In order to use locate command, the database should be created with the command:

sudo /usr/libexec/locate.updatedb

How to remove ^M from file using VI

Sometimes DOS files have "^M" at the end of each line, which causes problem for perl to read lines correctly.

We can use VI to remove these annoying ^M.

=============Using VI================

Type the following command at the terminal.

vi file_name.txt

Basically vi is the name of a text editor under linux/mac.

After issuing this command, you should be able to see the command window showing the content of the file.

Next step is to remove the annoying ^M at the end of each line.

Type the following command in VI editor. Do not miss the semi-colon at the begining.

:%s/[ctrlkey+v and ctrl-key+M]/\r/g

You should be able to see the following at the left-bottom corner of the command window:

:%s/^V^M/\r/g

The command above is meant to replace ^M with a new line symbol "\n".

Press enter and wait for a while for every occurrence of ^M to be replaced.

Depending on the size of your file, it can take a while and the screen appears frozen.

When the replacing is done, type the following command to save and exit from VI.

:x

Good luck!