Sindbad~EG File Manager

#define MAX_SESSIONID 33
#include <sys/types.h>
#include <time.h>
#define MAXBODIES 12
#define MAXSTEPS 100000

typedef  struct body3
{
   double mass;
   int bodynumber;
   int color;  // use RGB macro to specify
   double r;   // pixel coordinates of radius to use drawing it
   double x0,y0;   // initial position (world coordinates)
   double p0,q0;   // initial velocity (not momentum despite p,q)
}  body;

typedef struct docdata3
	{
		char sessionId[MAX_SESSIONID];     // key for hashing this structure
		UT_hash_handle hh;   //  makes this structure hashable
		time_t lastMessageTime;
		int pxmin, pxmax, pymin, pymax;  // pixel coordinates of the viewport
      double tmin, tmax;   // first and last t-values
      double xmin,xmax,ymin,ymax;   // world coordinates
      unsigned border, background;   // colors in RGB for the viewport
      unsigned nbodies;   // number of bodies
      char integrationMethod[32];   // "rk4" or "leapfrog", later maybe others
      int graphpaper;            // index of graph paper if we decide to support this
      body bodies[MAXBODIES];  //zero-based, it's an array
	}  DOCDATA3;
	
typedef DOCDATA3 *PDOCDATA3;
void init_docData3(PDOCDATA3 pDocData, char *sessionId, char*param);
int sendDocument3(PDOCDATA3);
int process_message3(PDOCDATA3 pDocData, char *message, char *param, char *outbuffer, int OUTBUFFER_SIZE);
int drawSolution(PDOCDATA3 pDocData);
void drawAxes(PDOCDATA3 pDocData);
void computeSolution(PDOCDATA3 pDocData);