Adding comma to end of each line if more than 1 line

Shell Programming and Scripting
1

I have a file with dates as

'2013-01-01'
'2013-01-02'

I want the output to be

'2013-01-01','2013-01-02'

if there is only 1 entry then there should not be any comma.

2

Try:

perl -0ne '$,=",";print split /\n/;print "\n"' file
3

i cannot be using perl command

4

Try :

$ awk '{printf "%s%s",NR==1 ? "" : OFS,$0}END{printf RS}' OFS=, file 
'2013-01-01','2013-01-02'

---------- Post updated at 02:24 AM ---------- Previous update was at 02:00 AM ----------

OR

$ tr -s '\n' ',' <file | sed 's/,$/\n/g'
5 
paste -sd, - <infile
6

I think it could be made even shorter:

paste -sd, infile
7

cat Sample | tr "\n" ","