On Tue, 30 Oct 2001, Stolz.Eric wrote:
> Hello list,
>
> I have a Problem with the printk function in a kernel module.
[snip]
> d_Result = (DOUBLE) l_InputValue / (DOUBLE) l_OffsetValue;
> printk("d_Result: %f\n", d_Result);
[snip - printf '%f']
/kernel/path/kernel/printk.c
asmlinkage int printk(const char *fmt,...)
{
...
/* Emit the output into the temporary buffer */
va_start(args, fmt);
printed_len = vsnprintf(printk_buf, sizeof(printk_buf), fmt,
args);
va_end(args);
...
}
we see vsnprintf does the work. ok, let's look at it, at
/kernel/path/lib/vsprintf.c
as you can see, the resason you got '%f' in the output is because the
kernel does not recognize the '%f' format specifier - in other words, no
floating point support in printk.
--
mulix
http://www.pointer.co.il/~mulix/
http://syscalltrack.sf.net/
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