Accessing a custom indicator

I have a free custom indicator (as a ex4 file) which I would like to reference from an EA. All I need is access to the information displayed in the data window - the value of the indicator at a bar. Logically speaking it should be possible to get this information, since the metatrader software has access to it. Any ideas how I can do this from an EA?

Logically speaking it should be explained in the manual.
vitali_yv:
Logically speaking it should be explained in the manual.

Got it once I realised you did not mean the manual for the indicator.

Works very nicely indeed.

https://docs.mql4.com/indicators/iCustom
Precisely