You should re-read the docs more closely:
Returns the number of bytes actually read, 0 at end of file, or undef if there was an error (in the latter case $! is also set).
"What should it profit a man, if he should win a flame war, yet lose his cool?"

In reply to Re^3: explanation for sysread and syswrite by Joost
in thread explanation for sysread and syswrite by bahadur

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