Re: runsv and EAGAIN

["Dražen Kačar" <dave@fly.srk.fer.hr>]

Charlie Brady wrote:
> >Here's a sample strace:
> >
> >rt_sigprocmask(SIG_UNBLOCK, [TERM], NULL, 8) = 0
> >rt_sigprocmask(SIG_UNBLOCK, [CHLD], NULL, 8) = 0
> >poll([{fd=3, events=POLLIN}, {fd=9, events=POLLIN, revents=POLLIN}, 
> >{fd=11, events=POLLIN}], 3, 1000020) = 1

You only have POLLIN in revents for fd 9. Also, the return value is 1,
meaning that only one file descriptor has readable data.

> >rt_sigprocmask(SIG_BLOCK, [TERM], NULL, 8) = 0
> >rt_sigprocmask(SIG_BLOCK, [CHLD], NULL, 8) = 0
> >read(3, 0xbfa256c3, 1)                  = -1 EAGAIN (Resource temporarily 
> >unavailable)
> >waitpid(-1, 0xbfa256bc, WNOHANG)        = 0
> >read(9, "", 1)                          = 0
> >read(11, 0xbfa256c3, 1)                 = -1 EAGAIN (Resource temporarily 
> >unavailable)
> >gettimeofday({1215792640, 591768}, NULL) = 0
> ...

> So poll i saying that data is available, and read is saying that it isn't. 
> Is anyone else confused?

poll() is saying that the data is available on fd 9 and read() on fd 9
does not return an error. The other two file descriptors should have not
been read.

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