Sybase does not have build-in support for outputting queries in CSV format. BCP has support for CSV but you probably do not want to down that route.
Here is one way of outputting the result of your query in CSV format. I will use the Sybase pubs2 example as the database. (the pubs2 example comes with all versions of Sybase).
Here is the contents of my shell script
isql -Uname -Ppassword -Sserver -Dpubs2 -b -h -w200 <<EOF | sed -e 's/ //g'
select '"',au_id,'","',au_fname,'","',au_lname,'","',phone,'"' from authors
go
EOF
Here is the output generated by the shell script
"172-32-1176","Johnson","White","408496-7223"
"213-46-8915","Marjorie","Green","415986-7020"
"238-95-7766","Cheryl","Carson","415548-7723"
"267-41-2394","Michael","O'Leary","408286-2428"
"274-80-9391","Dick","Straight","415834-2919"
"341-22-1782","Meander","Smith","913843-0462"
"409-56-7008","Abraham","Bennet","415658-9932"
"427-17-2319","Ann","Dull","415836-7128"
"472-27-2349","Burt","Gringlesby","707938-6445"
"486-29-1786","Chastity","Locksley","415585-4620"
"527-72-3246","Morningstar","Greene","615297-2723"
"648-92-1872","Reginald","Blotchet-Halls","503745-6402"
"672-71-3249","Akiko","Yokomoto","415935-4228"
"712-45-1867","Innes","delCastillo","615996-8275"
"722-51-5454","Michel","DeFrance","219547-9982"
"724-08-9931","Dirk","Stringer","415843-2991"
"724-80-9391","Stearns","MacFeather","415354-7128"
"756-30-7391","Livia","Karsen","415534-9219"
"807-91-6654","Sylvia","Panteley","301946-8853"
"846-92-7186","Sheryl","Hunter","415836-7128"
"893-72-1158","Heather","McBadden","707448-4982"
"899-46-2035","Anne","Ringer","801826-0752"
"998-72-3567","Albert","Ringer","801826-0752"