extract specified contents from two files.

src_dir=$(pwd)/All_h
dst_dir=$(pwd)/All
diff_dir=$(pwd)/diff

if [ ! -d $diff_dir ]
then
	mkdir $diff_dir
fi

for src_full_entry in $src_dir/*
do
	src_cat_entry=$(echo $src_full_entry | sed -e "s/.[0-9a-rA-F]{8}$//")
	src_cat_entry=$(basename "$src_cat_entry")
	src_ivr_log="$src_full_entry/de_ivr.log"
	if [ -f "$src_ivr_log" ]
	then
		#echo "$src_cat_entry"
		dst_ivr_log=$(find $dst_dir -regextype posix-egrep -regex ".*/$src_cat_entry.[0-9A-Fa-f]{8}/ivr.log$")
		#echo $dst_ivr_log
		if [ -f "$dst_ivr_log" ]
		then
			diff_ivr_log="$diff_dir/$src_cat_entry.diff"	
			summary="$diff_dir/$src_cat_entry""_summary.txt"
			#echo $diff_ivr_log
			#diff -u "$src_ivr_log" "$dst_ivr_log" > "$diff_ivr_log"
		
			echo "" > "$summary"			

			echo "##########################################################" >> "$summary"
			echo "$src_ivr_log:" >> "$summary"
			echo "##########################################################" >> "$summary"
			grep -i -n -A 20 "$src_cat_entry" "$src_ivr_log" >> "$summary"

			echo "" >> "$summary"
			echo "##########################################################" >> "$summary"
			echo "" >> "$summary"

			echo "##########################################################" >> "$summary"
			echo "$dst_ivr_log:" >> "$summary"
			echo "##########################################################" >> "$summary"
			grep -i -n -A 20 "$src_cat_entry" "$dst_ivr_log" >> "$summary"
			#diff -u "$src_ivr_log" "$dst_ivr_log" 
		fi
	fi
done

　　

if we want to use regular expressions for find command, we can do it like this.

find $dst_dir -regextype posix-egrep -regex ".*/$src_cat_entry.[0-9A-Fa-f]{8}/ivr.log$"