Re: Segmentation Fault Question

[Harring Figueiredo <harringf yahoo com>]

 No, it does not happen on fuction display:

 Here is what is happening:

 gdb> starting program: /home/harringf/downloads/a.out a.out

Program received signal SIGSEGV, Segmentation fault.
g_string_maybe_expand (string=0x80490cc, len=1) at gstring.c:88
88      {
(gdb) where
#0  g_string_maybe_expand (string=0x80490cc, len=1) at gstring.c:88
#1  0x40405a40 in g_string_insert_c (string=0x80490cc, pos=-1, c=47 '/') at
gstring.c:543
#2  0x404056a8 in g_string_append_c (string=0xa188b852, c=81 'Q') at
gstring.c:452
#3  0x08048e4d in permittedsyscall (regs=0xbfffdc50) at sandbox.c:60
#4  0x08049074 in main (argc=2, argv=0xbfffdd04) at sandbox.c:108
#5  0x420156a4 in __libc_start_main () from /lib/tls/libc.so.6


  So, if you go to sandbox.c at line 60; you will find:

  fpath = g_string_append_c (fpath, (char)nextword);


  Now, if you go to g_string_append source on glib/string.c, you will see:
GString*
g_string_append_c (GString *string,
                   gchar    c)
{
  g_return_val_if_fail (string != NULL, NULL);

  ...
}

 So, you never initialized you path (Gstring* path;).

 Make sure you initialise you  'path' variable inside that function.

 
 Regards.  (by the way, I could not compile your code because there was a
gtk_buttonnew_... that should have been gtk_button_new...)


Regards, Harring.


  

--- Mel Harbour <mrh30 cam ac uk> wrote:
> I've managed to narrow the problem down a bit.  The segmentation fault
> occurs when the function display() calls gtk_window_new.  Does anyone
> have any ideas what gtk_window_new is doing to cause a segfault here?
>
> Mel
>
> Mel Harbour wrote:
> > Appologies if this isn't the right place to post this!
> >
> > A program I'm writing, using GTK, is failing to run correctly.  In short 
> > it throws out a segmentation fault the first time I call something gtk 
> > related other than gtk_init.
> >
> > My code is at http://www.srcf.ucam.org/~mrh30/sandbox.c
> > with header file sandbox.h from the same address.
> >
> > The fault originates somewhere in the function permittedsyscall.  If I 
> > comment out the line 'display();' in the above function, the program 
> > runs as expected and will output a list of all the files opened by the 
> > program run through the sandbox.
> >
> > If you get rid of the code to extract those filenames and put the 
> > display() line back in, it also runs (apparently) correctly, putting a 
> > window up on screen.
> >
> > If I have both however, I get segmentation faults, which I would have 
> > thought was quite odd since neither part has any dealings with the other 
> > part.
> >
> > Mel
> >
> > _______________________________________________
> > gtk-app-devel-list mailing list
> > gtk-app-devel-list gnome org
> > http://mail.gnome.org/mailman/listinfo/gtk-app-devel-list
>
>
>
>
> _______________________________________________
> gtk-app-devel-list mailing list
> gtk-app-devel-list gnome org
> http://mail.gnome.org/mailman/listinfo/gtk-app-devel-list


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