Re: Fwd: Bug#21810: libc6: rexec call dumps core with user="string"and password=NULL

[Mark Kettenis <kettenis at wins dot uva dot nl>]

   Date: Tue, 26 Oct 1999 00:43:47 -0700
   From: Joel Klecker <espy@debian.org>

   >On Tue, Sep 28, 1999 at 01:24:30AM -0400, Raul Miller wrote:
   >> On Tue, Sep 28, 1999 at 02:20:46PM +1000, Herbert Xu wrote:
   >> > OK. What happened is that libc6 broke rexec(3) by not prompting when
   >> > the user/password is not set, then this was incorrectly fixed in
   >> > rexec.
   >>
   >> I can't find anything in the libc docs about prompting for rexec.
   >>
   >> What is libc6 doing wrong?
   >
   >Historically the rexec(3) would prompt for the username/password if the
   >arguments were null.  libc6 changed this, i.e., it now segfaults rather
   >than prompting for them.

Do you have any evidence that the statement about rexec asking for the
username/password is true?  Although the BSD man pages do indeed
mention that rexec() would do this, none of the BSD's derived from
BSD 4.2 (which according to the man page is the first version that has
rexec()) do implement this.  Since the code in glibc is derived
directly from BSD, it is no surprise that glibc doesn't do this
either.  So the whole issue appears to be a documentation bug on the
side of BSD.  There may be some reimplementations of rexec() around
that do ask for a password based on the BSD documentation,  but that's
not very relevant.  I think that there are a lot of cases where it is
unwanted.  As a principle, no library call should print anything
(except when that's the explicit purpose of the call of course), let
alone ask for input.

People that want the rexec to ask for a password, should implement
their own alternative.

Mark