Hi linuxppc-embedded?
In the device driver, we always want to send some data to the
application . So I was thinking , the IPC would do me a favor . I used the
sys_msgget and sys_msgsnd in the module ,but I got this when I type the "insmod
module" command :
insmod: unresolved symbol sys_msgget
insmod: unresolved symbol sys_msgsnd
In my opinion ,the system call is the system call to the user
application and the function to the kernel mode (eg: module ),so how to use the
system call in kernel mode is the way that how to recognise the function of
system call in the module .
At the beginning, I had to open and read a file in the module ,
so I used this way to add the system call :
#define _KERNEL_SYSCALLS_
#include <linux/unistd.h>
When I typed the "insmod module ",the symbol open and read
could be found ,but the function was not availability.So I checked the
/proc/ksyms for the function which the kernel could call , and used the
filp_open () and kernel_read () for instead .
Now , I did a test , compile the module with the linux kernel,
the sys_msgget and sys_msgsnd could work fine . I thought the reason is that
the sys_msgget is an extern function when compiling with the kernel.So perhaps
, when I do insmod the module, I did not exporte the sys_msgget and sys_msgsnd
as the kernel symbols.
How to exporte the system call as the kernel symbols??
Any help on this would be greatly appreciated. Thanks for your patience.
??zjznliang
????zjznliang_popo at 163.com
??????2005-11-16
