Shell Programming and Scripting

A
B
C
D
E
F
G
H
I
J
K
L

'A', 'B', 'C', 'D', 'E',
'F', 'G', 'H', 'I', 'J',
'K', 'L'

sed -n "s/.*/'&',/;H;5~5{z;x;s/\n//g;p;};\${x;s/\n\|,$//g;p;}" file1.txt

awk '{T=T DL Q $1 Q ","} !(NR%5) {print T; T=""} END {sub (/,$/, _, T); print T}' Q="\047" file1
'A','B','C','D','E',
'F','G','H','I','J',
'K','L'

perl -pe 's/(^|\n)/\047/g; (!eof)?{($.%5)?{$_.=", "}:{$_.=",\n"}}:{$_.="\n"}' FILE1.txt

'A', 'B', 'C', 'D', 'E',
'F', 'G', 'H', 'I', 'J',
'K', 'L'

sed '
:loop
$!{
N
/\(.*\n\)\{4\}/!b loop
}
s/^/'\''/
s/$/'\''/
s/\n/'\'','\''/g
$!s/$/,/
' FILE1.txt

sed '
:loop
$!{
N
x; s/$/a/; /a\{4\}/b exit
x; b loop
:exit
s/.*//
x
}
s/^/'\''/
s/$/'\''/
s/\n/'\'','\''/g
$!s/$/,/
' FILE1.txt

while read i;do
((count++))
 if [ $count -lt 5 ]
 then
 echo -ne ${i},
else
echo $i
count=0
echo -ne "\n"
 fi
 done < file