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Subjectparameters passing problem in driver module
Date
In application program ,code for call to write system call is given
below...
#include<fcntl.h>
main()
{
int count,fd;
fd=open("/dev/pseudo",O_RDWR);
write(fd,buff,5);
}

In driver module code for getting the buffer and count

#include<all related header files...>

int psuedo_write(struct inode*in,struct file*fp,char *buf,int count)
{
kprintf("<1>pseudo_write routine called \n");
kprintf("<1>count=%d \n",count);
kprintf("<1>buffer=%s \n",buff);
return 0;
}
/******so here after inserting the module into the kernel using insmod
pseudo.o and executing the application cc -c pseudo_app.c, the o/p on
console is *****/

"pseudo_write routine called"
"count=9988345352" /*garbage*/
"buffer=@#%h" . /*garbage*/

/*** but neither the buffer is carried from user space to kernel space nor
the count, why?***/Please help me
out.


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