or download this
$ strace perl -e'1 while read(STDIN, $buf, 512)' <a 2>&1 | grep 'read(
+0'
read(0, "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"..., 8192) = 8192
...
read(0, "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"..., 512) = 512
read(0, "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx", 512) = 32
read(0, "", 512) = 0