You are assuming that 1) its getting truncated, 2) perl is truncating it. You can't verify the output by what you see in your console. Example

C:\>perl -e "print qq,\r$_, for 1 .. 3"
3
C:\>perl -e "print qq,\r$_, for 1 .. 3" |hexdump
00000000: 0D 31 0D 32 0D 33       -                         | 1 2 3|
00000006;
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