Shell Programming and Scripting

#!/bin/sh
ps -ef | egrep talling
StoreThisLastCommandA=$_
awk '/error/ {print $3}' /tmp/test
StoreThisLastCommandB=$_

 ps -ef | egrep talling

awk '/error/ {print $3}' /tmp/test

OS:
RedHat
CentOS
Fedora
AIX
Raspian
Ubuntu

Shell: 
/bin/sh

cat script.ksh
trap 'previous_command=$this_command; this_command=$BASH_COMMAND' DEBUG
ps -ef | egrep talling
StoreThisLastCommandA=$previous_command
awk '/error/ {print $3}' /tmp/test
StoreThisLastCommandB=$previous_command
##Printing the variables values here.
echo "Value of variable StoreThisLastCommandA is: " $StoreThisLastCommandA
echo "Value of variable StoreThisLastCommandB is:" $StoreThisLastCommandB

#!/bin/sh
CommandA='ps -ef | egrep talling'
eval $CommandA
CommandB='awk '\''/error/ {print $3}'\'' /tmp/test'
eval $CommandB

#!/bin/sh
while read cmdline
do
  eval $cmdline
done <<'_EOF'
ps -ef | egrep talling
awk '/error/ {print $3}' /tmp/test
_EOF