> From: Joachim Schmitz [mailto:jojo@xxxxxxxxxxxxxxxxxx] > Sent: Wednesday, September 05, 2012 2:58 PM > To: 'Paolo Bonzini' > Cc: 'Junio C Hamano'; 'git@xxxxxxxxxxxxxxx'; 'Erik Faye-Lund'; 'bug-gnulib@xxxxxxx' > Subject: RE: poll() emulation in git > > > From: Paolo Bonzini [mailto:paolo.bonzini@xxxxxxxxx] On Behalf Of Paolo Bonzini > > Sent: Wednesday, September 05, 2012 2:05 PM > > To: Joachim Schmitz > > Cc: 'Junio C Hamano'; git@xxxxxxxxxxxxxxx; 'Erik Faye-Lund'; bug-gnulib@xxxxxxx > > Subject: Re: poll() emulation in git > > > > Il 05/09/2012 13:24, Joachim Schmitz ha scritto: > > > However: this poll implementation, while compiling OK, doesn't work properly. > > > Because it uses recv(...,MSG_PEEK), it works on sockets only (returns ENOTSOCK on anything else), while the real poll() works on all > > > kind if file descriptors, at least that is my understanding. > > > > Actually recv(...,MSG_PEEK) on most Unix variants works on non-sockets > > too. The trick is taken from GNU Pth in turn. > > > > > Here on HP NonStop, when being connected via an non-interactive SSH, we get a set of pipes (stdin, stdout, stderr) instead of a > > > socket to talk to, so the poll() just hangs/loops. > > > > Does your system have a working FIONREAD ioctl for pipes? > > It does have FIONREAD ioctl. Whether it works properly is to be determined... > I'll test if you could show me how? Oh, now I see what you aimed at, but no, that Mac OS X method doesn't work for me, I tried (at least I think I did). And <sys/ioctl.h> has /* * Normal IOCTL's supported by the socket interface */ #define FIONREAD _IOR(0, 8, _ioctl_int) /* Num of bytes to read */ #define FIONBIO _IOW(0, 9, _ioctl_int) /* Non-blocking I/O */ So these seem to be supported on sockets only, I guess. And indeed the man pages for ioctl confirms: Valid values for the request parameter for AF_INET or AF_INET6 sockets are: FIONREAD Gets the number of bytes available for reading and stores it at the int pointed at by arg. So not even AF_UNIX sockets, not to mention pipes... Bye, Jojo -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html