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Re: Meaning of sysread()

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Nicholas Clark
May 21, 2003 11:00
Re: Meaning of sysread()
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On Wed, May 21, 2003 at 05:54:17PM +0100, Nick Ing-Simmons wrote:
> Mark Mielke <> writes:
> >
> >Here is another argument:
> >
> >sysread() is documented ('man perlfunc') to '[attempt] to read LENGTH
> >characters of data ... [bypassing] buffered IO ...'. If Perl sysread()
> >is actually implemented using C read(), then it would be impossible to
> >read LENGTH characters of data, and only LENGTH characters of data
> >without calling C read() once for each byte. Remember - no buffering.
> You read LENGTH bytes and see how many characters that is.
> You find it is LENGTH-N chars so you read N more bytes and see where 
> you are ... 

I always assumed (note, assumed, not RTFM, read the Camel Book or read
the source) that sysread and syswrite make precisely 1 system call per
perl level call.

Or would this be where I need POSIX::read (etc)?

Nicholas Clark

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