I am afraid, you can not delete one (or more) line with Lite-C or C-Script.
AFAIK to do that, you have to make a loop to read the file, line by line, and write out those line what you want to keep into a new file.
Here is a pseudo code:
open for input(original file)
open for write(temporary file)
loop while(not EOF)
read from(original)
if(we need that line)
write to(temporary)
end if
end loop
close(original file)
close(temporary file)
delete(original file)
rename(temporary to original)