Hello,
I am very new to kernel development and I was playing around with
making modules. I found I could not retrieve commandline parameters in
the module if the parameter has whitespace in it. I thought it was my
lack of knowledge that was causing the error (and I still do
honestly), but I made a forum post here
http://forum.kernelnewbies.org/read.php?17,1354 regarding the issue,
and someone suggested it may be a bug and I should post on LKML.
The forum post shows example code to demonstrate the issue. I am using
archlinux and the latest kernel. I am not sure what other information
you need, so feel free to ask for anything.
Thanks
have a look around kernel/params.c
/* You can use " around spaces, but can't escape ". */
/* Hyphens and underscores equivalent in parameter names. */
static char *next_arg(char *args, char **param, char **val)
Your printks are probably showing the single quotes? probably not what
you want in your name
On Mon, Feb 8, 2010 at 5:56 AM, Larry Homes <[email protected]> wrote:
> Hello,
>
> I am very new to kernel development and I was playing around with
> making modules. I found I could not retrieve commandline parameters in
> the module if the parameter has whitespace in it. I thought it was my
> lack of knowledge that was causing the error (and I still do
> honestly), but I made a forum post here
> http://forum.kernelnewbies.org/read.php?17,1354 regarding the issue,
> and someone suggested it may be a bug and I should post on LKML.
>
> The forum post shows example code to demonstrate the issue. I am using
> archlinux and the latest kernel. I am not sure what other information
> you need, so feel free to ask for anything.
>
>
> Thanks
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to [email protected]
> More majordomo info at ?http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at ?http://www.tux.org/lkml/
>
No, the problem is not that the quotes are showing. The problem is
that as soon as it sees a space, it assumes the following is the next
parameters name. So for example:
[root@myhost modules]# insmod hello3.ko name="john smith"
insmod: error inserting 'hello3.ko': -1 Unknown symbol in module
[root@myhost modules]# insmod hello3.ko "name=john smith"
insmod: error inserting 'hello3.ko': -1 Unknown symbol in module
In both cases, dmesg shows:
hello3: Unknown parameter `smith'
I looked at the params.c code and it seems like the above should work.
On Sun, Feb 7, 2010 at 5:14 PM, andrew hendry <[email protected]> wrote:
> have a look around kernel/params.c
> /* You can use " around spaces, but can't escape ". */
> /* Hyphens and underscores equivalent in parameter names. */
> static char *next_arg(char *args, char **param, char **val)
>
> Your printks are probably showing the single quotes? probably not what
> you want in your name
>
> On Mon, Feb 8, 2010 at 5:56 AM, Larry Homes <[email protected]> wrote:
>> Hello,
>>
>> I am very new to kernel development and I was playing around with
>> making modules. I found I could not retrieve commandline parameters in
>> the module if the parameter has whitespace in it. I thought it was my
>> lack of knowledge that was causing the error (and I still do
>> honestly), but I made a forum post here
>> http://forum.kernelnewbies.org/read.php?17,1354 regarding the issue,
>> and someone suggested it may be a bug and I should post on LKML.
>>
>> The forum post shows example code to demonstrate the issue. I am using
>> archlinux and the latest kernel. I am not sure what other information
>> you need, so feel free to ask for anything.
>>
>>
>> Thanks
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>> the body of a message to [email protected]
>> More majordomo info at ?http://vger.kernel.org/majordomo-info.html
>> Please read the FAQ at ?http://www.tux.org/lkml/
>>
>
On 13:13 Mon 08 Feb , Larry Homes wrote:
> No, the problem is not that the quotes are showing. The problem is
> that as soon as it sees a space, it assumes the following is the next
> parameters name. So for example:
>
> [root@myhost modules]# insmod hello3.ko name="john smith"
> insmod: error inserting 'hello3.ko': -1 Unknown symbol in module
>
> [root@myhost modules]# insmod hello3.ko "name=john smith"
> insmod: error inserting 'hello3.ko': -1 Unknown symbol in module
>
> In both cases, dmesg shows:
>
> hello3: Unknown parameter `smith'
>
> I looked at the params.c code and it seems like the above should work.
I'm not familiar with the code in question, but I suspect that it
expects to actually see the quotation marks in the parameter value, but
your shell is eating them. Try
insmod hello3.ko 'name="john smith"'
instead.
--
Nick Bowler, Elliptic Technologies (http://www.elliptictech.com/)
That was it. The shell was eating the quotes. Thanks alot!
On Mon, Feb 8, 2010 at 1:43 PM, Nick Bowler <[email protected]> wrote:
> On 13:13 Mon 08 Feb ? ? , Larry Homes wrote:
>> No, the problem is not that the quotes are showing. The problem is
>> that as soon as it sees a space, it assumes the following is the next
>> parameters name. So for example:
>>
>> [root@myhost modules]# insmod hello3.ko name="john smith"
>> insmod: error inserting 'hello3.ko': -1 Unknown symbol in module
>>
>> [root@myhost modules]# insmod hello3.ko "name=john smith"
>> insmod: error inserting 'hello3.ko': -1 Unknown symbol in module
>>
>> In both cases, dmesg shows:
>>
>> hello3: Unknown parameter `smith'
>>
>> I looked at the params.c code and it seems like the above should work.
>
> I'm not familiar with the code in question, but I suspect that it
> expects to actually see the quotation marks in the parameter value, but
> your shell is eating them. ?Try
>
> ?insmod hello3.ko 'name="john smith"'
>
> instead.
>
> --
> Nick Bowler, Elliptic Technologies (http://www.elliptictech.com/)
>
On Tue, Feb 9, 2010 at 2:47 AM, Larry Homes <[email protected]> wrote:
> That was it. The shell was eating the quotes. Thanks alot!
>
When you met quote problems like this, just test them with echo. ;)
In this case, try:
echo name="john smith"
Hope this helps.