I'm want to read a string from file
this string is for example

```
&0001 = 1234 5678 9abc

```

now I want to take this string and build another string from it which is

```
123456789abc

```

I succeeded to read the the string from the end of the file by 

```
read_addr="`awk "END {print}" file.txt`"
echo ${read_addr}

```

how should I continue to create the string 123456789abc out of the above?