This is a method of changing the keymap used for copy/history mode. The string is made up of oldchar=newchar pairs which are separated by ‘:’. Example: The command
markkeys h=^B:l=^F:$=^Ewould set some keys to be more familiar to
emacsusers. If your terminal sends characters, that cause you to abort copy mode, then this command may help by binding these characters to do nothing. The no-op character is `@' and is used like this:
markkeys @=L=Hif you do not want to use the `H' or `L' commands any longer. As shown in this example, multiple keys can be assigned to one function in a single statement.