$ bc $(grep 'hda$' /proc/partitions | awk '{ print$3 }') '-' $(awk '/hda[0-9]/ { i+= $3 } END { print i }' /proc/partitions)
File 80418240 is unavailable.
stompthebozo@sarge:~$
stompthebozo@sarge:~$ echo $3 + $1  $(grep 'hda$' /proc/partitions | awk '{ print$3 }') '-' $(awk '/hda[0-9]/ { i+= $3 } END { print i }' /proc/partitions)
+ 80418240 - 80413295
stompthebozo@sarge:~$ echo $3 + $1  $(grep 'hda$' /proc/partitions | awk '{ print$3 }') '-' $(awk '/hda[0-9]/ { i+= $3 } END { print i }' /proc/partitions) | bc
(standard_in) 1: parse error
stompthebozo@sarge:~$ echo $3 + $1 ; $(grep 'hda$' /proc/partitions | awk '{ print$3 }') '-' $(awk '/hda[0-9]/ { i+= $3 } END { print i }' /proc/partitions) | bc
+
bash: 80418240: command not found
stompthebozo@sarge:~$ echo 3 + 1 ; $(grep 'hda$' /proc/partitions | awk '{ print$3 }') '-' $(awk '/hda[0-9]/ { i+= $3 } END { print i }' /proc/partitions) | bc
3 + 1
bash: 80418240: command not found
stompthebozo@sarge:~$ echo 3+1 ; $(grep 'hda$' /proc/partitions | awk '{ print$3 }') '-' $(awk '/hda[0-9]/ { i+= $3 } END { print i }' /proc/partitions) | bc
3+1
bash: 80418240: command not found
stompthebozo@sarge:~$ echo 3+1 $(grep 'hda$' /proc/partitions | awk '{ print$3 }') '-' $(awk '/hda[0-9]/ { i+= $3 } END { print i }' /proc/partitions) | bc
(standard_in) 1: parse error
stompthebozo@sarge:~$ echo 3+1 ; $(grep 'hda$' /proc/partitions | awk '{ print$3 }')  $(awk '/hda[0-9]/ { i+= $3 } END { print i }' /proc/partitions) | bc
3+1
bash: 80418240: command not found
stompthebozo@sarge:~$ echo 3 + 1 ; $(grep 'hda$' /proc/partitions | awk '{ print$3 }')  $(awk '/hda[0-9]/ { i+= $3 } END { print i }' /proc/partitions) | bc
3 + 1
bash: 80418240: command not found
stompthebozo@sarge:~$ echo $3 + $1  $(grep 'hda$' /proc/partitions | awk '{ print$3 }')  $(awk '/hda[0-9]/ { i+= $3 } END { print i }' /proc/partitions) | bc
(standard_in) 1: parse error
stompthebozo@sarge:~$ echo $3 + $1 ; $(grep 'hda$' /proc/partitions | awk '{ print$3 }')  $(awk '/hda[0-9]/ { i+= $3 } END { print i }' /proc/partitions) | bc
+
bash: 80418240: command not found