#include <stdlib.h>
  long atol( const char *str );

The function atol() converts str into a long, then returns that value. atol() will read from str until it finds any character that should not be in a long. The resulting truncated value is then converted and returned. For example,

   x = atol( "1024.0001" );		
		

results in x being set to 1024L.