I don't really understand how the size command works, so say
if I'm in /tmp and I have a file called 'hello'. What I want
to do is determine the size of the size 'hello' and store the
size size as 'size_of_hello'
eg: size -s "/tmp/hello" = "size_of_hello"
I have no idea where you have found a size command. Its not a
perl builtin. On my Solaris workstation I have an executable called size, but it is used to print the sizes
of sections in object files, probably not what you want.