Setting GPIO pins n linux

Is it possible to set GPIO pins in userspace? If I include gpio.h from the
source code, will the followig lines be valid for example?
 
//first number is the pin number on the schematic
#define CE_H __gpio_set_value(27, 1)
#define SCK_H __gpio_set_value(26,1)
#define MISO_H __gpio_set_value(24,1)
#define MOSI_H __gpio_set_value(25,1)

Thanks!

Just read kernel's Documentation/gpio.txt

http://www.avrfreaks.net/wiki/index.php/Documentation:Linux/GPIO