Re: g_serial hangs on write when the cable is disconnected

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Wed, Aug 05, 2015 at 11:05:56AM +0100, Laszlo Papp wrote:
> Hi,
> 
> The code below reproduces the issue. The code is intentionally kept
> small, so it deliberately does not have error checking, et al.
> 
> Now, my concern is that it blocks for the write operation if the cable
> is disconnected. This is not inline with the /dev/ttyS* operation, for
> instance. They would not block if I disconnected the serial cable.
> 
> Is this a bug or feature? :-) If it turns out to be a feature, is it
> better to use O_NONBLOCK if one does not want to use pthreads, etc?
> 
> #include <sys/types.h>
> #include <sys/stat.h>
> #include <fcntl.h>
> 
> int main()
> {
>     const char buf[] = "Hello World!\n";
>     int fd = open("/dev/ttyGS0", O_RDWR | O_NONBLOCK);

This line discipline is very different from the "traditional" tty line
discipline, so it might not know anything about cable removals.

good luck,

greg k-h
--
To unsubscribe from this list: send the line "unsubscribe linux-serial" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html



[Index of Archives]     [Kernel Newbies]     [Security]     [Netfilter]     [Bugtraq]     [Linux PPP]     [Linux FS]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Samba]     [Video 4 Linux]     [Linmodem]     [Device Mapper]     [Linux Kernel for ARM]

  Powered by Linux