On Thu, Oct 6, 2011 at 6:43 PM, Yang Xiang <pointyx@xxxxxxxx> wrote: > Hi Greg, > > Let me rephrase my question then. > > If I am in kernel space and in another device driver and I need to write a > log entry of some sort to another block device, do I just perform an "open" > and "write" as if I am in user space? > > I am very new at this so bear with me on this. > > Thanks in advance. > yx First, always post replies at the bottom of messages on kernel mailing lists. Note how I had to delete much of the earlier thread in order to reply properly. Second, If by log, you mean output text based log messages: The standard behavior is you log your messages to the ring buffer. (kprintf and family will do that for you.) Then userspace pulls it out of the ring buffer and writes it to a file (or block device). Your distro probably uses syslogd or rsyslogd for the userspace side. It is highly configurable and you can setup a dedicated logfile for just you. If you mean more of a binary transaction log like a filesystem uses, then it gets more complicated. There are very few kernel drivers that maintain a transaction log on a dedicated block device. I don't know how they do it, but I'd look at filesystem code the supports an external partition for the transaction logs. HTH Greg (not KH) _______________________________________________ Kernelnewbies mailing list Kernelnewbies@xxxxxxxxxxxxxxxxx http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
