On Wed, 28 Nov 2012, Alexander Varnin wrote:
> Hello!
> I'm trying to add UIO device to my system to handle interrupt. But i'm
> facing following problem. Docs says, on reading device /dev/uio0 it will
> block until interrupt occurs. I've made simple program for test. It
> tries to write 1 to enable interrupts.
>
> #include <unistd.h>
> #include <errno.h>
> #include <fcntl.h>
> #include <stdio.h>
>
> int main()
> {
> int fd;
> char c = 1;
> fd = open("/dev/uio0", O_RDONLY);
> if (fd<0) {
> printf("open error: %d\n", errno);
> return 0;
> }
> printf("fd == %d\n", fd);
> int res = write(fd, &c, 1);
> if(res<0) {
> printf("write error: %d\n", errno);
> }
> return 0;
> }
>
open O_RDONLY and then write to it ?
return of 9 == EBADF
man 2 write
EBADF fd is not a valid file descriptor or is not open for writing.
hofrat
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