Also, is read guaranteed to return the number of bytes requested (if the file is big enough)? sysread isn't.

Could you clarify this for me?

From sysread:

sysread ... Returns the number of bytes actually read, 0 at end of file, or undef if there was an error ...

Under what circumstances would sysread fail to return the number of bytes actually requested?

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
Lingua non convalesco, consenesco et abolesco. -- Rule 1 has a caveat! -- Who broke the cabal?
"Science is about questioning the status quo. Questioning authority".
The "good enough" maybe good enough for the now, and perfection maybe unobtainable, but that should not preclude us from striving for perfection, when time, circumstance or desire allow.

In reply to Re^4: Speed reading (files) by BrowserUk
in thread Speed reading (files) by kwaping

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