need Unix script help

This is Unix script assgnment in class. I have a students list named:classdb.txt

ID:NAME:Course1:course2
001:Harry:Comp123:Comp234

I have to write a script to add new student in the list.
I think should use the "sed" command, but is not working.
please help.
this is what I have try:
echo enter the students ID
read num
echo enter the students name
read name
echo enter the course name
read class1
echo enter the course name
read class2
$sed -f classdb

所有跟帖： 

• 回複：need Unix script help -kv2388- ♂ (41 bytes) () 11/07/2004 postreply 13:43:42

• thanks a lot! -@~!@#$%^&*- ♀ (0 bytes) () 11/07/2004 postreply 18:05:01

• 順便問一句，怎麽刪除一個用戶呢？如果隻是給了用戶名？ -thanks!!#- ♀ (0 bytes) () 11/07/2004 postreply 18:08:03

• 回複：順便問一句，怎麽刪除一個用戶呢？如果隻是給了用戶名？ -kv2388- ♂ (63 bytes) () 11/07/2004 postreply 21:19:22

• correction: $tmpfile->tmpfile -kv2388- ♂ (0 bytes) () 11/07/2004 postreply 21:21:12

• gao shou thanks a lot -!@#$%- ♀ (0 bytes) () 11/08/2004 postreply 15:47:48