How to mouse copy a very long line in vim terminal OS X
You can use a little trick: save that long line to a temp file and copy that.


Select the desired portion of the line by moving the cursor to the first good position. By pressing v f [character], you select everything from that position to the next occurence of [character]. Pressing v $ would select to the end of that line. Use the power of Vim to select just the portion of the text you need.
Write the selection to a temp file by typing :w /tmp/long_line.
If the command already starts with :'&lt;,'&gt;, that's fine (it's a mark for your selection), just type ahead: :'&lt;,'&gt;w /tmp/long_line
Exit Vim and process the /tmp/long_line file as you like. A simple solution would be cat /tmp/long_line and selecting the output


Alternative: Buy a larger screen ;)