It would be nice if the perl docs on sysread were clearer on the question of partial reads. The word "Attempts" is inadequate: of *course* sysread will *attempt* to read. After all, if the file contains fewer bytes than requested, or if the file is a terminal or some such, then an *attempt* to read more bytes than are available will result in a partial read.

But the perl docs should be clearer about whether sysread will ever read fewer bytes than requested in cases where those bytes *are* available to be read. As is, a cautious programmer must assume that partial reads could happen for no apparent reason, and from the above discussion this sounds like it is the case. But it would be nice if the documentation made this clear, both to help those who might not notice this subtle case and to avoid wasting the time of those who do notice and spend time trying to find the answer in the docs.

Anybody know where to make this suggestion? I didn't see any indication on the perlfunc page.


In reply to Re: sysread and syswrite in tcp sockets by dbooth
in thread sysread and syswrite in tcp sockets by rustybar

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