//gcc -Wall formfloat.c -o formfloat `pkg-config --libs --cflags gtk+-2.0`
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
//#include </usr/include/glib-2.0/glib.h>
#include <gtk/gtk.h>		// pour glib ?

void formfloat(char *ss,double ff)	// sup decimales a 0 et ., si besoin
{
int i,j,ll;
char *s1 = ss;
sprintf(s1,"%f",ff);
ll=strlen(s1);
for ( i = ll-1; i >0; --i)	{
  if ( s1[i] == '0')	{
   s1[i] = '\0';
   j = i -1;
   if ( s1[j] == '.' || s1[j] == ',')
     { s1[j] = '\0'; break; }
			}
  else break;
				}
}

int main(int argc, const char *argv[])
{
int i;
double fl;
char ss[20];
char sp[]="1234.5678901";
char sv[]="1234,5678901";
fl = 10.31313002;
for ( i=1; i<10; ++i)	{
  formfloat(ss,fl);
  printf("i=%d fl=%f s= '%10s'\t %d\n",i,fl,ss,(int)strlen(ss));
  fl /= 5;
			}
printf("\n");
// virgules
fl = 10,31313002;
for ( i=1; i<10; ++i)	{
  formfloat(ss,fl);
  printf("i=%d fl=%f s= '%10s'\t %d\n",i,fl,ss,(int)strlen(ss));
  fl /= 5;
			}
printf("\n");
  fl = g_strtod(sp,NULL);
  formfloat(ss,fl);
  printf("point fl=%f s= '%10s'\t %d\n",fl,ss,(int)strlen(ss));
printf("\n");
  fl = g_strtod(sv,NULL);
  formfloat(ss,fl);
  printf("virgule %s fl=%f s= '%10s'\t %d\n",sv,fl,ss,(int)strlen(ss));
printf("\n si strlen(ss) >= 20 le prog devrait planter\n\n");

fl = 12345.678901;
for ( i=1; i<15; ++i)	{
  formfloat(ss,fl);
  printf("i=%d fl=%f s= '%10s'\t long_ss=%d\n",i,fl,ss,(int)strlen(ss));
  fl *= 100;
			}
return (EXIT_SUCCESS);
}