[syslog-ng] syslog-ng on hp-ux

Balazs Scheidler [email protected]
Fri, 3 Mar 2000 11:39:09 +0100


> snip from: "man 2 read":
> 
>       When attempting to read from an empty pipe or FIFO:
> 
>            +  If no process has the pipe open for writing, read() will
>               return 0 to indicate end-of-file.
> 
>            +  If some process has the pipe open for writing and O_NONBLOCK
>               is set, read() will return -1 and set errnoto EAGAIN.
> 
>            +  If some process has the pipe open for writing and O_NONBLOCK
>               is clear, read() will block until some data is written or the
>               pipe is closed by all processes that had the pipe open for
>               writing.
> 
> syslog-ng will open /dev/log  - try to read from /dev/log and will recive end-of-file.
> syslog-ng closes /dev/log and open the file again - try to read from /dev/log and
> recieve end-of-file - etc. etc.

thanks for the explanation. What does poll() return on pipes with no writer
processes? If syslog-ng maxes out the CPU it most probably means that poll()
returns that the pipe is readable.

-- 
Bazsi
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