Messages in this thread | | | Date | Mon, 06 Jul 2009 08:30:16 +0200 | From | Albert ARIBAUD <> | Subject | Re: PROPOSAL: extend pipe() to support NULL argument. |
| |
Changli Gao a écrit : > On Mon, Jul 6, 2009 at 2:15 PM, Albert ARIBAUD<albert.aribaud@free.fr> wrote: >>> >>> pipe doesn't support llseek. >> I wasn't thinking of actively seeking a file position, but simply that reads >> and writes were independent (and both variable) in size, thus even without >> (l)seeking, each endpoint has an independent read (resp. write) position to >> track what's been read from (resp.written into) it at any time, and such a >> position is, IIUC, single for a given fd, making a fd (a struct file) >> insufficient for representing a pipe. >> >> Amicalement, >> -- >> Albert. >> > pipe doesn't refer to pos when reading or writing. Please refer to > pipe_read() and pipe_write() for more detail.
Hmm. Then how does pipe avoid overwriting what it's already written at the in endpoint, or reading twice the same data from the out endpoint?
Amicalement, -- Albert. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |