Retrieve last field in each line

[et_phonehome_2]

I want to read a line from a text file, and am interested in assigning the last field to a variable.  How do I do this without hardcoding the position, I want the script to be flexible enough to handle varying number of columns.

[Dusty]

Is the 'text' file space delimited?

[Salmon Trout]

We have been asked to supply script code to extract the last "field" from a line of text, but we have not been told how the fields are delimited. Dusty has already asked about this. Until this is known, it will be difficult to provide a suitably robust solution.