provides virtual half-line and reverse line feed sequences
for terminals without such capability, and on which overstriking
Half-line characters and underlining (changed to dashing `-')
are placed on new lines in between the normal output lines.
Suppress all underlining.
This option is especially useful for previewing
Causes all half-lines to be printed, effectively double spacing the output.
Normally, a minimal space output format is used which will suppress empty
The program never suppresses two consecutive empty lines, however.
option is useful for sending output to the line printer when the output
contains superscripts and subscripts which would otherwise be invisible.