Geografic-Information-System/imagery/i.modis.qc/mod09A1sh.c

/* MOD35 snow/ice flag unsigned int bits [12]
 * 0 -> class 0: Yes
 * 1 -> class 1: No
 */  

#include <grass/raster.h>

CELL mod09A1sh(CELL pixel) 
{
    CELL qctemp;

    pixel >>= 12;
    qctemp = pixel & 0x01;

    return qctemp;
}