Re: ITP: fakedate

[Russell Coker <russell@coker.com.au>]

On Wed, 26 May 1999, you wrote:
>on linux-kernel there was once a posting for an app, that could trap any
>system call and make the kernel return different results.
>think like strace, but allows to reprogram system calls.
>
>i'm sorry, i don't know where the program was,
>but maybe you like to search and look at this approach.

Thanks for the suggestion however I don't plan to take that approach.  Firstly
all good programs should be dynamically linked to libc and therefore all date
related functions can be subverted by just wrappering library calls.  I could
write some sort of debugger which intercepted system calls but that would take
more effort and would require tracing programs right through.  This would not
work for inetd spawned daemon processes, SUID processes, or the situations
where the current version of GDB fails to follow program execution (currently
I've only seen this fail in non-trivial programs such as gcc so I haven't filed
a bug report).  I presume that if I were to write my own debugger to do this
then I wouldn't do it as well as the GDB people.
My work is aimed at Y2K testing well written applications.  Badly written
applications (statically linked to libc) can be presumed to fail in any
millennium.  ;)  So I don't feel inclined to write software to test them.

As for shareware, the old version of the Frauhoffer MPEG layer 3 audio encoder
(l3enc) would run for a period of 30 days after you downloaded it (see there is
date restricted software for Linux).  Also companies such as Computer
Associates, Cisco, and others release time limited trial versions of their
products for Solaris (this is shareware IMHO).  I presume that most such
companies have products for Solaris x86 if not Linux native applications.  I'm
sure that anyone who has been in the position of having their manager purchase
such software and lose the key would have a good use for my library.


--
I am in London and would like to meet any Linux users here.
I plan to work in London until April and then move to another
place where the pay is good.