Listing 1: A Sample Shell Script Interface

# NLQ fonts

courier=0
sansserif=1
prestige=3
boldps=6

# Justification codes

left=0
center=1
right=2
leftright=3

# Variables

nlq=no
font=$courier
progpitch=0
justify=$left
tab4=no

for i in $options
do
case $i in
nlq)
nlq=yes
;;
font=* )
font=`parse ${i}`
font=`eval echo $"$font"`
;;
pica)
progpitch=0
;;
elite)
progpitch=`expr $progpitch + 1`
;;
prop)
progpitch=`expr $progpitch + 2`
;;
compressed)
progpitch=`expr $progpitch + 4`
;;
emph)
progpitch=`expr $progpitch + 8`
;;
double)
progpitch=`expr $progpitch + 16`
;;
wide)
progpitch=`expr $progpitch + 32`
;;
italic)
progpitch=`expr $progpitch + 64`
;;
underline)
progpitch=`expr $progpitch + 128`
;;
justify=* )
justify=`parse ${i}`
justify=`eval echo $"$justify"`
;;
tab4)
tab4=yes
;;
esac
done

# Reset the printer no matter what else is happening

echo "\033@\c"

# Set the Near Letter Quality mode & NLQ font style

if [ "$nlq" = yes ]
then
echo "\033x1\c"
echo "\033k${font}\c"
fi

# Set the programmable pitch/highlighting
#   This combines the following modes:
#   underlining, italic, double width, double print, emphasized,
#   compressed, proportional spacing, and elite/pica
# The syntax seems a bit convoluted, but the value delivered to the ESC-!
# printer command must be a binary value.  Since echo works with octal, the
# awk command simply replaces the decimal value with the octal equivalent.
# The "hard part" was getting echo to use it: echo must have that leading zero!

progpitch=`echo ${progpitch} | awk '{printf("%03o",$0)}'`
echo "\033!\\0${progpitch}\c"

# Set the justification
#   0 = Left aligned (normal)
#   1 = Centered between margins
#   2 = Right aligned
#   3 = Left/Right justified

echo "\033a${justify}\c"

# Set tab stops every 4 positions

if [ "$tab4" = yes ]
then
echo "\033D\004\010\014\020\024\030\034\040\044\050\054\060\064\070\074\000\c"
fi