Shell Programming and Scripting

#!/usr/bin/ksh
typeset -i mFirst5
typeset -i mLast5

mFirstLine=$(head -1 inp_file)
mFirst14=$(echo ${mFirstLine} | cut -d'|' -f1-4)
mFirst5=$(echo ${mFirstLine} | cut -d'|' -f5)
mFirst5=${mFirst5}+1
mFirstOut=${mFirst14}'|'${mFirst5}

mLastLine=$(tail -1 inp_file)
mLast14=$(echo ${mLastLine} | cut -d'|' -f1-4)
mLast5=$(echo ${mLastLine} | cut -d'|' -f5)
mLastRest=$(echo ${mLastLine} | cut -d'|' -f6)
mLast5=${mLast5}+1
mLastOut=${mLast14}'|'${mLast5}'|'${mLastRest}

sed -e "1s/.*/${mFirstOut}/" -e "\$s/.*/${mLastOut}/" inp_file