Hello world build error!

[Altera_Forum]

Hi all, 

When build the hello_world.c, I encount a error, Is any one can help me out? the hello_world.c as follows: #include <linux/init.h># include <linux/module.h># include <linux/kernel.h> static int hello_init(void) { printk (KERN_ALERT "Hello, world!\n"); return 0; } static void hello_exit (void) { printk (KERN_ALERT "Goodbye, cruel world\n"); } module_init (hello_init); module_exit (hello_exit); MODULE_LICENSE("Dual BSD/GPL"); and the problem as follows: $ nios2-linux-uclibc-gcc linux-2.6.x/drivers/misc/hello.c -o hello -elf2flt="-s 4000" In file included from /opt/nios2/lib/gcc/nios2-linux-uclibc/3.4.6/../../../../nios2-linux-uclibc/sys-include/linux/sched.h:16,                 from /opt/nios2/lib/gcc/nios2-linux-uclibc/3.4.6/../../../../nios2-linux-uclibc/sys-include/linux/module.h:9,                 from linux-2.6.x/drivers/misc/hello.c:6: /opt/nios2/lib/gcc/nios2-linux-uclibc/3.4.6/../../../../nios2-linux-uclibc/sys-include/linux/signal.h:2:2: warning:# warning "You should include <signal.h>. This time I will do it for you." In file included from /opt/nios2/lib/gcc/nios2-linux-uclibc/3.4.6/../../../../nios2-linux-uclibc/sys-include/linux/sched.h:79,                 from /opt/nios2/lib/gcc/nios2-linux-uclibc/3.4.6/../../../../nios2-linux-uclibc/sys-include/linux/module.h:9,                 from linux-2.6.x/drivers/misc/hello.c:6: /opt/nios2/lib/gcc/nios2-linux-uclibc/3.4.6/../../../../nios2-linux-uclibc/sys-include/linux/resource.h:2:2: warning:# warning "You should include <sys/resource.h>. This time I will do it for you." In file included from /opt/nios2/lib/gcc/nios2-linux-uclibc/3.4.6/../../../../nios2-linux-uclibc/sys-include/asm/cache.h:25,                 from /opt/nios2/lib/gcc/nios2-linux-uclibc/3.4.6/../../../../nios2-linux-uclibc/sys-include/linux/cache.h:5,                 from /opt/nios2/lib/gcc/nios2-linux-uclibc/3.4.6/../../../../nios2-linux-uclibc/sys-include/linux/module.h:10,                 from linux-2.6.x/drivers/misc/hello.c:6: /opt/nios2/lib/gcc/nios2-linux-uclibc/3.4.6/../../../../nios2-linux-uclibc/sys-include/asm/nios.h:4:26: nios2_system.h: No such file or directory In file included from linux-2.6.x/drivers/misc/hello.c:6: /opt/nios2/lib/gcc/nios2-linux-uclibc/3.4.6/../../../../nios2-linux-uclibc/sys-include/linux/module.h:41: error: field `attr&#39; has incomplete type /opt/nios2/lib/gcc/nios2-linux-uclibc/3.4.6/../../../../nios2-linux-uclibc/sys-include/linux/module.h:49: error: field `kobj&#39; has incomplete type linux-2.6.x/drivers/misc/hello.c: In function `hello_init&#39;: linux-2.6.x/drivers/misc/hello.c:14: error: `KERN_ALERT&#39; undeclared (first use in this function) linux-2.6.x/drivers/misc/hello.c:14: error: (Each undeclared identifier is reported only once linux-2.6.x/drivers/misc/hello.c:14: error: for each function it appears in.) linux-2.6.x/drivers/misc/hello.c:14: error: syntax error before string constant linux-2.6.x/drivers/misc/hello.c: In function `hello_exit&#39;: linux-2.6.x/drivers/misc/hello.c:19: error: `KERN_ALERT&#39; undeclared (first use in this function) linux-2.6.x/drivers/misc/hello.c:19: error: syntax error before string constant  It says the 'KERN_ALERT' was not declared, but what try 'make', it has no problem.  Is that it need include other files in hello_world.c? How to build executable file for nios independent? I hope anyone can help me out? ths!

[Altera_Forum]

didn't you try 

make ARCH=nios2nommu CROSS_COMPILE=nios2-linux-uclibc- -C ~/uClinux-dist/linux-2.6.x M=`pwd` modules  which you will need to compile device drivers   instead of  nios2-linux-uclibc-gcc linux-2.6.x/drivers/misc/hello.c -o hello -elf2flt="-s 4000" which suits for user programm.  You will find detailed explanation in the kernel docs.  hope this helps, but i'm not a kernel crack maybe you take a look at the nioswiki for the module programming example.  by the way let me ask you, what do you want to do? do you want to write a device driver or a user program.

[Altera_Forum]

--- Quote Start ---  originally posted by helmchen@Feb 3 2007, 10:52 PM didn&#39;t you try make arch=nios2nommu cross_compile=nios2-linux-uclibc- -c ~/uclinux-dist/linux-2.6.x m=`pwd` modules  which you will need to compile device drivers    instead of  nios2-linux-uclibc-gcc linux-2.6.x/drivers/misc/hello.c -o hello -elf2flt="-s 4000" which suits for user programm.  you will find detailed explanation in the kernel docs.  hope this helps, but i&#39;m not a kernel crack maybe you take a look at the nioswiki for the module programming example.  by the way let me ask you, what do you want to do? do you want to write a device driver or a user program. <div align='right'><{post_snapback}> (index.php?act=findpost&pid=21184)</div>  --- Quote End ---   hi Helmchen,  thank you very much for your reply, I&#39;m porting uCLinux on my own NiosII board, and start develope programme according to hippo&#39;s post: http://forum.niosforum.com/forum/index.php?showtopic=3174 (http://forum.niosforum.com/forum/index.php?showtopic=3174)  when come to 11 tips, I have tied code he provided: ----------------- nios2-linux-uclibc-gcc hello.c -o hello -elf2flt cp hello ~/rootfs/bin Rebuild the kernel image for initramfs, boot nios2 uClinux, and run hello -----------------  Here the &#39;hello.c&#39; is a user programme, I mistake it to a device driver, and use nios2-linux-uclibc-gcc linux-2.6.x/drivers/misc/hello.c -o hello -elf2flt="-s 4000"  which is applied for user programme, so got the errors.  Now I write a "hello world" user programme, and compiled successfully according the code.  Thanks again!  And I have a question:  I have make a "hello_world" module which is a simple device driver, but I can only dynamic add it by "modprobe hello_world".  Do you know how to add it with static method,namely add this module in when the kernel start?

[Altera_Forum]

<div class='quotetop'>QUOTE </div> 

--- Quote Start ---  Do you know how to add it with static method,namely add this module in when the kernel start?[/b]  --- Quote End ---    Again please read about module programming in the nioswiki.  nioswiki/module programming (http://nioswiki.jot.com/wikihome/operatingsystems/%c2%b5clinux/moduleprogramming)

[Altera_Forum]

<div class='quotetop'>QUOTE </div> 

--- Quote Start ---  Do you know how to add it with static method,namely add this module in when the kernel start?[/b]  --- Quote End ---    Device Drivers --> Misc devices ---> <*> example hello module  Press <Space> several times to select the mode of the driver, <M> is module <*> is static linked to kernel < > unselect

[Altera_Forum]

I want to know where i can find the hello module after the image is download into the DE2.Is it in the dir of /bin? but i can not find it.

[Altera_Forum]

--- Quote Start ---  originally posted by liuxiaoping@Mar 25 2007, 09:57 PM i want to know where i can find the hello module after the image is download into the de2.is it in the dir of /bin? but i can not find it. <div align='right'><{post_snapback}> (index.php?act=findpost&pid=22486)  --- quote end ---    --- Quote End ---   All kernel modules will be in the /lib/modules/ <kernel version> tree. Don&#39;t mix up kernel modules with user apps.

[Altera_Forum]

To hippo: 

I am very sorry for my mistake,in fact,i did not find the module in the dir /lib,not /bin.In the dir of bin,i use the command ls,but there is only a file,i don&#39;t know why?

[Altera_Forum]

Make sure you have the hello.c in linux-2.6.x/drivers/misc, and you have updated Kconfig an Makefile in that dir. 

After "make" and "make linux images", in the uClinux-dist dir, please check if you have the hello.ko "tree linux-2.6.x/drivers/misc" "tree romfs/lib"   Or you may check some other drivers or fs as modules, and find the modules of them.