cnrdean@cavebear.berkeley.edu (05/24/91)
Anybody know of some standard C code (I need it for Turbo C) that will make a program not work after a particular date? Thanks. Sam
rearl@watnxt3.ucr.edu (Robert Earl) (05/24/91)
In article <1991May23.221811.21343@agate.berkeley.edu> cnrdean@cavebear.berkeley.edu writes: | Anybody know of some standard C code (I need it for Turbo C) | that will make a program not work after a particular date? Yeah, how about: t = time(0L); :-) -- ______________________________________________________________________ \ robert earl / "Love is a many splintered thing" rearl@watnxt3.ucr.edu \ --Sisters of Mercy rearl@gnu.ai.mit.edu /
pt@geovision.gvc.com (Paul Tomblin) (05/24/91)
cnrdean@cavebear.berkeley.edu writes: >Anybody know of some standard C code (I need it for Turbo C) >that will make a program not work after a particular date? The best, and only unbreakable method of doing this is to fire up your trusty word processor, and send them a letter saying that after that date, you are not going to provide tech support, upgrades, and all the other stuff that a REAL program should come with. (If it doesn't come with that stuff, why would people pay for it, since any copy protection can be broken) TRUE STORY: At my last job, we had an evaluation copy of MOSS (a terrain modelling system), that we were licensed to use for one pilot project, finishing at a certain date. Well, due to political reasons, the project went over time, but we didn't want MOSS to stop working. We suspected that the MOSS evaluation copy had one of these stupid "stop working after such-and-such-date" routines in it, so we wrote a dummy versions of all the routines that return the system date, and patched the executable. It then continued for the rest of the pilot, at which point we got authorization to get the REAL version. So much for trying to make programs blow up at a certain date. -- Paul Tomblin, Department of Redundancy Department. ! My employer does Two roads diverged in a wood, and I/ I took the one less ! not stand by my travelled by/ And that is why I'm lost, dammit... ! opinions.... pt@geovision.gvc.com or {cognos,uunet}!geovision!pt ! Me neither.
enag@ifi.uio.no (Erik Naggum) (05/26/91)
"Sam" writes: | | Anybody know of some standard C code (I need it for Turbo C) | that will make a program not work after a particular date? I'm looking for some standard C code which will make a program WORK after a particular date. Any takers? </Erik> -- Erik Naggum Professional Programmer +47-2-836-863 Naggum Software Electronic Text <ERIK@NAGGUM.NO> 0118 OSLO, NORWAY Computer Communications <enag@ifi.uio.no>
richard@aiai.ed.ac.uk (Richard Tobin) (05/28/91)
In article <ENAG.91May26161252@gyda.ifi.uio.no> enag@ifi.uio.no (Erik Naggum) writes: >I'm looking for some standard C code which will make a program WORK >after a particular date. Any takers? I know of many programs that could benefit from such code :-) -- Richard -- Richard Tobin, JANET: R.Tobin@uk.ac.ed AI Applications Institute, ARPA: R.Tobin%uk.ac.ed@nsfnet-relay.ac.uk Edinburgh University. UUCP: ...!ukc!ed.ac.uk!R.Tobin
shane@inferno.peri.com (Shane Bouslough) (05/29/91)
cnrdean@cavebear.berkeley.edu writes: > > Anybody know of some standard C code (I need it for Turbo C) > that will make a program not work after a particular date? > This is a specific example of the general problem of software copy protection. No method is foolproof. One simple technique is to write a date at the end of the .exe and have the program open the file and compare this date to the current date. This doesn't trash the .exe since the loader knows when to stop reading. Finding the location of the .exe and other anti-copy protection problems are left as an exercise. Interestingly, I wrote a short 10 liner to do this for a friend and it worked for Zortech and Microsoft but failed for Turbo. -- Shane Bouslough | ...!rutgers!mcdhup!inferno!shane 516-467-0500 Periphonics Corp. | Ride Bike! 4000 Veterans Hwy. | "We're talking Mega-Ecstasy-Bliss!!!" Bohemia, NY 11716 | -David Lister, Red Dwarf
jja@wsl.ie (John Allen on wsl) (06/07/91)
In article <1991May29.165444.6387@inferno.peri.com> shane@inferno.peri.com (Shane Bouslough) writes: > >This is a specific example of the general problem of software >copy protection. No method is foolproof. One simple technique >is to write a date at the end of the .exe and have the program >open the file and compare this date to the current date. This >doesn't trash the .exe since the loader knows when to stop reading. > >Interestingly, I wrote a short 10 liner to do this for a friend and >it worked for Zortech and Microsoft but failed for Turbo. > Any chance of telling us why the Turbo version did'nt work, let's see the code. ----------------------------------------------------------------------------- |\/\/\/| | | | (-)(o) | _) | ,___| | / /____\ And the BART raised up his hands and said unto the masses. People that don't know want to know from the people that do know and if the poeple that do know don't tell the people that don't know then the people that don't know still won't know. "Don't quote me on any issue whatsoever, unless you feel oblidged to."