Hi,

I am writing a server program, I have to use accept() to get information fro
m client, at the same time i set a timer (using setitimer()) to do some peri
odical jobs(just some data update), but every time the timer function is inv
oked, the accept() will return with error. This always happens when the time
r is invoked the second time, no matter what interval I set to it. This stil
l happens when I put accept() and timer setup in two threads.

Anyone met this problem before?? Who can help me?
Thanks

Tian

[ Post a follow-up to this message ]

quote:

> "Wang Tian News" <wangtian@cs.unc.edu> wrote in message news:3fcb7b54
> $1_2@news.unc.edu...

quote:

> I am writing a server program, I have to use accept() to get information

from client,
quote:

> at the same time i set a timer (using setitimer()) to do some periodical

jobs(just some
quote:

> data update), but every time the timer function is invoked, the accept()

will return with
quote:

> error. This always happens when the timer is invoked the second time, no

matter what
quote:

> interval I set to it. This still happens when I put accept() and timer

setup in two threads.

When you use 'setitimer', it's supposed to interrupt a blocking
function. I'm not sure why this is a problem for you. When 'accept' returns
with an error, just do the periodic jobs and call 'accept' again.

If you're going to use threads, don't use 'setitimer' since there's
nothing to interrupt. If you need to delay, just use 'nanosleep', 'usleep',
'select', or whatever makes sense on your platform. Though a bit ugly,
'select(0, NULL, NULL,NULL, &tv);' works on every pthreads platform I know
of.

DS

[ Post a follow-up to this message ]

quote:

> "Wang Tian News" <wangtian@cs.unc.edu> wrote in message news:3fcb7b54
> $1_2@news.unc.edu...

quote:

> I am writing a server program, I have to use accept() to get information

from client,
quote:

> at the same time i set a timer (using setitimer()) to do some periodical

jobs(just some
quote:

> data update), but every time the timer function is invoked, the accept()

will return with
quote:

> error. This always happens when the timer is invoked the second time, no

matter what
quote:

> interval I set to it. This still happens when I put accept() and timer

setup in two threads.

When you use 'setitimer', it's supposed to interrupt a blocking
function. I'm not sure why this is a problem for you. When 'accept' returns
with an error, just do the periodic jobs and call 'accept' again.

If you're going to use threads, don't use 'setitimer' since there's
nothing to interrupt. If you need to delay, just use 'nanosleep', 'usleep',
'select', or whatever makes sense on your platform. Though a bit ugly,
'select(0, NULL, NULL,NULL, &tv);' works on every pthreads platform I know
of.

DS

[ Post a follow-up to this message ]