Re: why is this code here?

[Daniel Burrows <Daniel_Burrows@brown.edu>]

On Fri, Dec 10, 1999 at 01:39:07PM -0800, Sean 'Shaleh' Perry was heard to say:
> in dbootstrap/choose_medium.c:choose_NFS_server()
> 
> for (;;) {
>     /* keep user entry between calls to choose_NFS_server */
> 
>     if (!preventry) preventry=strdup(""); <<-- why??????
> 
>     nfsmountpath=inputBox(_("Please choose the NFS server and the mount path of
> the NFS filesystem that contains the Debian archive.\nEnter them in this way: 
> server:/ftp/debian"),_("Choose Debian NFS filesystem"),preventry);
>     if (! nfsmountpath) return 1;
>     free(preventry);
>     preventry=nfsmountpath;
> 
> .....
> }
>
> preventry is set to NULL at the top, strdup("") just sets it to NULL again. 
> What am I missing????

  Huh?  Unless the semantics of C strings have changed underneath me, strdup("")
sets it to *a pointer to* a NULL byte.  This is important, since otherwise
you'll segfault when you try to access strdup..assuming that inputBox doesn't
treat NULL strings as "".

  Daniel

-- 
  Believe in the Great God Om or be stricken with thunderbolts?
  Is that the way it always has to be?

             -- Terry Pratchett, _Small Gods_