Re: Zooming issues in interactive terminals

[Lutz M. <lut...@gm...>]

On Friday 16 May 2008 15:23:35 Ethan Merritt wrote:
> On Friday 16 May 2008 15:07, Lutz Maibaum wrote:
> > thanks for looking into this. I must admit I don't quite understand
> > your proposed changes to the scanner, but as a quick fix would it be
> > sufficient to replace the %g in the line above by %E, which always
> > includes a decimal point?
>
> That would probably fix it for the specific case of zooming,
> but the general case would still be broken.  As it stands, all integer
> constants in the input stream are silently truncated to LONG_MAX on
> a "normal" machine configuration.  Yours at least prints an error
> message.

According to the manpage of my standard C library (glibc 2.6.1 release 18.3 
for X86-64, openSUSE), atol does not check for overflow errors, whereas 
strtol does. It also has the following to say:

    You should not check for errors by examining the return value of
     `strtol', because the string might be a valid representation of
     `0l', `LONG_MAX', or `LONG_MIN'.  Instead, check whether TAILPTR
     points to what you expect after the number (e.g. `'\0'' if the
     string should end after the number).  You also need to clear ERRNO
     before the call and check it afterward, in case there was overflow.

Thanks again,

  Lutz