Scripting Help

I am tring to automate updating an IP address, username, and password for a PPTP client that I have. I have the files being parsed and and I have the router pulling them every hour.

Currently I have 3 files which are

ip.domain.com
(inside the file I have the IP address with no spaces)

un.domain.com
(inside the file I have the username with no spaces)

pw.domain.com
(inside the file I have the password with no spaces)

I would like to use the information inside of the files to update my pptp client.
/interface pptp-client set domain.com-pptp connect-to=/ip.domain.com user=/un.domain.com password=pw.domain.com

How would one accomplish this?

Was easier than I though.

:global variablename [/file get example.txt contents];

pass variable with

[$variablename]