Combine multiple lines between flags in one line in AWK

Question

Example file:

Pattern 1

AAAAAAAAAA
BBBBBBBBBB

Pattern 2

I want to print the lines between two patterns in a file in one line. From a previous question How to print lines between two patterns, inclusive or exclusive (in sed, AWK or Perl)? I found the very nice

awk '/Pattern 1/{flag=1; next} /Pattern 2/{flag=0} flag' file

With output:

AAAAAAAAAA
BBBBBBBBBB

My desired output:

AAAAAAAAAABBBBBBBBBB

Answer 1

You may use this awk:

awk '/Pattern 2/ {if (s!="") print s; s=f=""} f {s = s $0} /Pattern 1/ {f=1}' file

AAAAAAAAAABBBBBBBBBB