AWK: Extract text between two delimiters. Write each match to file/

extract_thread_dump.awk

# First thread dump line
/^Full thread dump Java/        {
  thread_dump=1; 
	counter++;
	lines=0;
	filename="Thread_dump_"counter".txt";
	printf "Found thread dump #%-4d\t", counter
}

# Last thread dump text block    
/^Heap[:space:]*$/ {
	thread_dump=2;
}

# Last thread dump line - first blank line after "Heap"
{ if (thread_dump==2 && $0 ~ "^[:space:]*$") {
	thread_dump=0;
	printf "(%5d lines)\n", lines;
     } 
}


# Print line only if in thread dump block
{ if (thread_dump!=0) { 
	print $0 > filename;
	lines++;		
	} 
}