Re: [Xenomai-help] select(2) generates EFAULT

[Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>]

Steve wrote:
> First, thank you for the help on my previous query.
> 
> I am still working on porting a c++ application from RTAI to Xenomai,
> and have encountered a problem with sockets, specifically the select
> function.
> 
> When Xenomai is not being used the code runs as expected.  Once the
> Xenomai headers, compile options, etc, are used the select function
> fails with the error EFAULT.  I have reproduced the error (works
> without Xenomai, EFAULTs with Xenomai) using the following program:
> 
> #include <stdio.h>
> #include <arpa/inet.h>
> #include <errno.h>
> 
> int handleError(char *msg, int err);
> 
> int main(void)
> {
>    int sfd;
>    struct sockaddr_in sai;
>    fd_set SockSet;
>    struct timeval tv;
>    tv.tv_sec = 2;
>    tv.tv_usec = 0;
> 
>    sai.sin_family = AF_INET;
>    sai.sin_port = htons(1025);
>    sai.sin_addr.s_addr = htonl(INADDR_ANY);
> 
>    if((sfd = socket(AF_INET, SOCK_STREAM, 0)) == -1)
>    { return handleError("creation error", errno); }
> 
>    if(bind(sfd, (struct sockaddr*)&sai, sizeof(sai)) == -1)
>    { return handleError("bind error", errno); }
> 
>    if(listen(sfd, 5) == -1)
>    { return handleError("listen error", errno); }
> 
>    FD_ZERO(&SockSet);
>    FD_SET(sfd, &SockSet);
> 
>    if(select(sfd+1, &SockSet, 0, 0, &tv) == -1)
>    { return handleError("select error", errno); }
> 
>    printf("success\n");
> 
>    return 0;
> }
> 
> I am using Xenomai 2.4.6.1 on a vanilla 2.6.24.6 Linux kernel, and
> running on Ubuntu 8.04.

Could you try 2.4.7, to see if you are not having a bug which has
already been fixed?

What you are trying should work, even though you are not really using
Xenomai's select but Linux plain select.

-- 
                                                 Gilles.