linux kernel print to file problem

Dear Linux-lovers.

I am trying to build a 2.6.10 linux kernel module to print messages to a
file. I have done this 2.4 and I was successful but I am failing here.

I am using the sys_open, sys_write calls to do so.
I am getting a compilation warning and I find no .ko file created
finally instead I find an .o.ko file.

*** WARNIG: "sys_write" [/home/cf.o.ko] undefined!
Below is the module code. Please suggest me what could be the problem:-


#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <asm/fcntl.h>          /* for O_WRONLY */
#include <linux/syscalls.h>     /* for sys_ functions */
#include <asm/uaccess.h>        /* for set_fs(), get_fs() etc. */
#include <linux/string.h>       /* for string length */
#include <linux/slab.h>         /* for kmalloc */

MODULE_LICENSE("GPL");
/*
#define DBG
#define PRINTK(fmt,arg...) printk("DBG INFO <%s> | "
fmt,__FUNCTION__,##arg)
#else
#define PRINTK(fmt,arg...) while(0)
#endif
*/

typedef struct tagWRITE_TEST
{
        unsigned long fd;
        unsigned long x;
        
}WRITE_TEST, *PWRITE_TEST;

PWRITE_TEST ptest;

void SysPrint(char * pString, ...)
{
        static char buff[1024];
        va_list ap;

        va_start(ap,pString);
        vsprintf((char *)buff, pString, ap);
        va_end(ap);
        
        sys_write(ptest->fd,(char *)buff,(size_t)strlen(buff));
}

int init_module(void)
{
        
        printk("<%s> invoked!\n",__FUNCTION__);
        printk("File Creation Testing in Kernel Module!\n");

        set_fs(get_ds());
        
        /* allocate the memory for structre */
        ptest = (PWRITE_TEST)kmalloc(sizeof(WRITE_TEST),GFP_KERNEL);
        if(ptest == NULL)
        {
                printk("Structure Memory Allocation Fails!\n");
                return -ENOMEM;
        }
        
        ptest->fd = sys_open("srcdebug.txt", O_CREAT | O_WRONLY, 644);
        if (ptest->fd == 0)
        {
                SysPrint("File Creation Error!!!\n");
                return 1;
        }
        
        SysPrint("File Creation Testing in Kernel Module!\n");
        SysPrint("Srinivas Testing the File Creation\n");
        sys_close(ptest->fd);
        
        return 0;
}

void cleanup_module(void)
{
        printk("Good bye!\n");

        /* free the allocated memory */
        kfree(ptest);
}

Regards,
Mukund jampala

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