Sysfs class attribute problem

Hello all

I am new to sysfs interface ans I read about in mochel's documentation. And doing some experiements on it. Let's come to Tue problem, in my module I have a global variable type char* myglobal and it s static, I am putting that value in my one and only class attribute using show function. But for the same if I a user put some value in to the using echo or something, the attribute value is not changing. And one more thing s after I passed the value to the attribute my system not shutting down :( . Please help me how to read values.

// in store function I am doing this:
Myglobal = bus;

Sent from my HTC

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