Getting 'bad file number' error writing to device driver

[Daniel Baluta]

Hello,

> I am trying to write to mydriver but get a 'Bad file number' error.
>
> int fd = open("/dev/mydriver",O_RDWR);
>
> this opens successfully as fd is not -1.
>
> ssize_t bytesToWrite = strlen(buf);
>
> value is: bytesToWrite 28
>
> ssize_t bytesWritten = write(fd,buf,bytesToWrite);
>
> value is: bytesWritten -1
>
> __android_log_print(ANDROID_LOG_INFO,__FILE__,"ANIL
> strerror(errno) %s",  strerror(errno));
>
> value is: strerror(errno) Bad file number

Please use strace and let us know the full trace of system calls.
Also, if possible
could you paste the 'write' function of your driver?

thanks,
Daniel.