fscanf of live stream question

Hello I have written the following code for counting how much '\n' chars we have so far.

i assume fscanf holds the char recieved in the live streaming but instead it shows val as an array of growing number.

and throws me the following error Matrix "dimensions must agree."

how can i check what char was recieved rigt now?

Thanks.

sObject=serial('COM4','BaudRate',115200,'TimeOut',10,'Terminator','LF')
fopen(sObject)
k=0;
while 1==1
   val=fscanf(sObject) 
    if val=='\n'
       k=k+1 
    end
    
end

[dpb]

If you have R2019b, use the serialport object instead of serial