Shell Programming and Scripting

%GOGG
doggocatcatFUNFUNGOGOHIHI
%SONSON
byetailfunfungo
%GOGG
hellobyebyetailfunfungoson
$SONSON
funfungogo

%GOGG
nfungosondoggocatc
%SONSON
unfungogobyetailfu

cat file | egrep -A 2 "%" | head -c15 > file.out

awk '
        {
                if ( $1 ~ /^%/ )
                {
                        A[$1]++
                        i = $1
                }
                else
                        R[A[i],i] = $0
        }
        END {
                for ( k in A )
                {
                        print k
                        print substr(R[A[k],k],length(R[A[k],k])-8) substr(R[1,k],1,9)
                }
        }
' file

awk '
$1~/^%/ {
  key=$1
  next
}
{
  if (key in s1) {
    s2[key]=substr($0,length($0)-8)
  } else {                     
    s1[key]=substr($0,1,9)
  }                  
}
END {               
  for (key in s1) {
    print key
    print s2[key] s1[key]
  }
}
' file

awk '
  /^%/{
    i=$1
    getline s
    A[i]=(i in A)?substr(s, length(s)-8) substr(A[i],1,9):s
  }
  END{
    for (i in A) {
      print i
      print A[i]
    }
  }
' file