Re: [Gcl-devel] 2.6.11 windows

[David Billinghurst]

On 4/09/2014 11:23 AM, Camm Maguire wrote:
> Greetings!
>
> Could you please try commenting out the following line of o/read.d:
>
>      if (n!=1||s[m]) return OBJNULL;
This works and prints 2.718281828459045 on the setq example

> If this works, then try replacing it with
>
>     printf("%s %d %d %lf\n",s,n,m,f);fflush(stdout);
>
> recompile, and try your setq example again.  Your C library
> implementation of sscanf cannot correctly process
>
>      n=sscanf(s,"%lf%n",&f,&m);
>
> and so far is the only such system that I have found.

The sscanf function stops at character 349, so next character is not the 
null terminating the string.
As shown, the strtod function works, so this may be an option.

mingw uses the microsoft MSVCRT library for I/O. I have done a search 
and can't find mention of this bug.

Here is a self contained test case.

#include <stdio.h>
#include <stdlib.h>

int main () {
  char s[]= "\
2.718281828459045235360287471352662497757247093699\
95957496696762772407663035354759457138217852516642\
74274663919320030599218174135966290435729003342952\
60595630738132328627943490763233829880753195251019\
01157383418793070215408914993488416750924476146066\
80822648001684774118537423454424371075390777449920\
69551702761838606261331384583000752044933826560297\
60673711320070932870912744374704723069697720931014\
16928368190255151086574637721112523897844250569536\
96770785449969967946864454905987931636889230098793\
12773617821542499922957635148220826989519366803318\
25288693984964651058209392398294887933203625094431\
173012381970684161404";
  int n, m;
  double f;
  char *endptr;

  n=sscanf(s,"%lf%n",&f,&m);
  printf("s    = %s\n",s);
  printf("n    = %d\n",n);
  printf("m    = %d\n",m);
  printf("f    = %lf\n",f);
  printf("s[m-2]:s[m] = %c%c%c\n",s[m-2],s[m-1],s[m]);

  /* try strtod
   *endptr is character that stopped scan */
  printf("\nWith strtod\n");
  f = strtod(s,&endptr);
  printf("f    = %lf\n",f);
  printf("len  = %d\n",endptr-s);
  if (! *endptr )
    printf("Terminating char is null\n");
  printf("Last char = %c\n",*(endptr-1));
 }


and the output

s    = 
2.7182818284590452353602874713526624977572470936999595749669676277240766303535475945713821785251664274274663919320030599218174135966290435729003342952605956307381323286279434907632338298807531952510190115738341879307021540891499348841675092447614606680822648001684774118537423454424371075390777449920695517027618386062613313845830007520449338265602976067371132007093287091274437470472306969772093101416928368190255151086574637721112523897844250569536967707854499699679468644549059879316368892300987931277361782154249992295763514822082698951936680331825288693984964651058209392398294887933203625094431173012381970684161404
n    = 1
m    = 349
f    = 2.718282
s[m-2]:s[m] = 297

With strtod
f    = 2.718282
len  = 621
Terminating char is null
Last char = 4