Syntax

I can't find good tutorial about syntax of / %.

In expect script I am trying to do something like this:

set size [file size $tp_receive_to_path]
# Now check if it return 0
if { $size mod 72 != 0 } {
# receive file! Retry
send -s -- "get $tp_receive_to_tmppath
$tp_receive_to_path\r"
}

Is syntax of if and mod correct ?

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