In unix, does the file size present is In byte format ?
-rw-r-----+ 1 stck stck 20340713 Mar 3 10:11 C44444.STC.112
Can you you tell me how to filter the file size which should be less than the file size "20340713" one in particular directory.
That depends on which tool you use and which options you supply. Above seems to be the output of ls defaulting to byte sizes. Be aware of the -h and -si options, see man ls , and of possible aliases of ls .
Did you consider the find -size utility?
That looks to be an "ls -l" command output which indeed outputs the size in bytes for regular files.
Beware that these options are GNU extensions so might not be present on the OP "ls".
try
ls -l folder | awk '$5<20340713'