Edlin: w (write)
Writes the first portion of the edited file from memory to a disk. Used without parameters, w writes lines from the edited file in memory to a disk until memory is 25 percent full.
n : Specifies the number of lines that you want to write to the disk, beginning with the first line of the edited file in memory.
? : Displays a list of edlin subcommands.
In this example, the final 100 lines of your disk file do not fit into memory. To free up enough space to load the remainder of your disk file into memory and continue editing, type: