6 ms·
Molly guard in reverse
https://en.wiktionary.org/wiki/molly-guard https://en.wiktionary.org/wiki/molly-guard
- jiehong 8mo agoOh! Then perhaps the long press required for the iPhone’s action button to trigger is a Molly guard! Also, perhaps `rm` should be molly guarded to move things to the trash on all systems by default, and delete only if forced to by a flag. Note: I’d have expected Molly to be a cat, because they tend to be pretty good at disrupting things in my experience.
- denkmoon 8mo agorm has mollyguarding, that's why every invocation of rm you see on the internet is followed by -f
- yjftsjthsd-h 8mo agoI think that may be a combination of (IMHO unfortunate) factors: * Yes, on some systems rm is aliased to rm -i by default. * Some scripts will use rm -f because normal rm returns an error if the target already doesn't exist but -f doesn't care. * Finally, sometimes files are just ... I think it's being marked read-only that does it? I've hit this while trying to rm a git checkout; you actually do need to add -f sometimes to succeed. So if you just add -f then it'll always work.
- Modified3019 8mo agoSeeing long presses implemented for those intermittent and irreversible actions in games is something I‘ve always appreciated. I often end up making errant inputs, especially on keyboards. A guard I often make for myself is removing/disabling the delete key on my keyboard, and setting FN+Backspace to Delete with whatever control software is involved. I often then repurpose the delete key location to F2, which is typically used to “Edit” a spreadsheet cell or file name.
- bookofjoe 8mo agoRed team demur: I HATE the iPhone's long press requirement to restart from off. To me, a button that forces me to wait for an unknown and indeterminate period of time before functioning is a FAIL.
- yjftsjthsd-h 8mo ago> Also, perhaps `rm` should be molly guarded to move things to the trash on all systems by default, and delete only if forced to by a flag. Not all systems, but some (RHEL, I think?) default alias rm='rm -i', yes
- deleted 8mo ago[deleted]
- jiehong 8mo agoI do wish those were a thing on flat touch sensitive induction cooktops! (For all those pesky water droplets causing the cooktop to error out and turning itself off)
- gib444 8mo agoI get annoyed even at the thought of those things! Had to use a few while travelling. Ugh!
- hyperhello 8mo ago“Mollyguarding” sounds like a great derogation of unnecessary safety measures. Stop mollyguarding me!
- Shadowmist 8mo agoI've been looking for this!
- evanjrowley 8mo agoI'm reminded of this legendary HN comment: https://news.ycombinator.com/item?id=16530398 https://news.ycombinator.com/item?id=16530398
- cortesoft 8mo agoI am confused by the second guy who was curious and punched the plastic lid… it says you have to hold the button down for 30 seconds, how did that happen?
- charles_f 8mo agoThe guard itself ends up pushing the button
- cortesoft 8mo agoAnd it can’t be lifted back up?
- evanjrowley 7mo agoPerhaps it could only be opened up with a key they did not have within 30 seconds reach - another safety mechanism that backfired in that specific scenareo.
- yolosollo 8mo ago[flagged]
- spongebobstoes 8mo agothis isn't like a Molly guard. this is like asking the toddler to be careful
- JoshTriplett 8mo agoThere's a great piece of software called "molly-guard", which intercepts calls to "poweroff" and "reboot" and similar. It checks if it's being invoked via an SSH session, and if so, it asks you to type the name of the system you're shutting down. That way, you never accidentally shut down a remote server when you meant to shut down your own system (or a different server).
- magicalhippo 8mo agoAnother fun one is disabling the network interface on a remote server. An acquaintance did that by mistake on a cloud VM running some core services, and the cloud provider had no virtual console for some reason. Ended up having to write off the VM and restore from backup. Fun day at the office.
- adrian_b 8mo agoLong ago, I succeeded once to cut my own access through SSH to a remote server, after some firewall changes. That of course has required a long trip to the server, for physical access. However that was good, because after that I have always been extra careful at any changes that could affect the firewall in any way. (That is not restricted to changes in firewall rules, because there are systems where the versions of the firewall program and of the kernel must be correlated, so an inconsistent update may make the firewall revert to its default state of denying all connections.)
- kqr 8mo agoI can warmly recommend the nohup-sleep-disable-cancel pattern for this, as a dead man's switch for danngerous changes. https://entropicthoughts.com/locking-yourself-out-with-firewall-config https://entropicthoughts.com/locking-yourself-out-with-firew...
- learn_more 8mo agoI previously managed a firewall via scripts which would automatically revert your update in 20 seconds unless interrupted. So if you botched it and lost access, you just had to sit tight for 20 seconds.
- itayd 8mo agobest molly-guard depicited in "The Good Place": https://www.youtube.com/watch?v=etJ6RmMPGko https://www.youtube.com/watch?v=etJ6RmMPGko
- fainpul 8mo agoJust please don't start adding molly-guards to your software. The concept only makes sense in the physical world, e.g. where the "important button", that you might never have to press, needs to be in reach all the time. In software, there are better solutions.
- fragmede 8mo agomy favorite Debian package is Mollyguard so when you shut down a server remotely via SSH it just checks the second time to make sure you really wanted to shut down that server and not your laptop.
- fainpul 8mo ago"Are you sure?" type guards are not suitable for actions which the user does regularly. If a user repeats this action regularly, they quickly automate the thought process (i.e. don't give it any thought anymore) and it becomes useless.
- selfhoster11 8mo agoWhich is why that's not what it does. It asks you to input the hostname instead, just like deleting a repo in Github does.
- fainpul 8mo agoI know how it works. Please don't nit-pick. It's an interruption that forces the user to confirm. That's what I meant. I discussed this also here: https://news.ycombinator.com/item?id=46845740 https://news.ycombinator.com/item?id=46845740
- fragmede 8mo agoIt's not nitpicking. The nature of the interruption being different is material. I've lost files to automatically answering yes to rm -i y/n confirm. Typing the hostname itself is different enough to get me, at least to stop and go wait, hold on. And snap me out of doing the wrong one. Especially an SSH gateway machine.
- 0xbadcafebee 8mo agoIn DevOps (and Lean, TPS) the more advanced form of this is the Poka-Yoke (https://en.wikipedia.org/wiki/Poka-yoke https://en.wikipedia.org/wiki/Poka-yoke). Poka-yokes don't just add safety, they also guide the human away from making a mistake. The canonical example is the automatic shift knob in a car. The shift knob is designed to 1) prevent you from accidentally shifting all the way back into reverse without pressing the shift button, and 2) prevents you from leaving park or neutral without depressing the brake pedal. This way you don't damage the drivetrain or accidentally cause the car to roll forward/backward. Poka-yoke is a form of defensive design (https://en.wikipedia.org/wiki/Defensive_design https://en.wikipedia.org/wiki/Defensive_design). For a beautiful example of defensive design, see the average electric kettle. If water boils over the top it won't short the device, if it boils dry it'll stop operating, the handle and body are plastic to prevent burning yourself, the handle is ergonomic to make carrying 1.5L of sloshing boiling water not cause you to spill it, the cord is detached from the kettle so you don't yank the cord and spill the boiling water, the switches are located on the bottom away from hot steam, and the lids usually lock while in operation, again to prevent damage from spillage or steam. It's the simplest and safest possible way to boil water, and it's $20.
- vharuck 8mo agoMy favorite example of poka-yoke is when the pieces and hardware in build-it-yourself furniture kits won't fit anywhere except the correct places: two screws only have the same width if they're interchangeable, wood bars refuse to go in unless facing the right direction, etc.
- graypegg 8mo agoThe example that comes to my mind is lockout tags. [0] It usually means temporarily jamming up a specific control marked as the lockout/ignition/energizing control while you're working on some big and gnarly machine. There's a bunch of regulation around the specifics of what that control has to prevent if not activated/lockedout, but usually it's a dirt-simple breaker switch or hydraulic valve, controlling whatever the main source of energy into the machine is. The ones with holes are for padlocks that everyone will lock padlocks onto so you have a count of who's still "down there". If you ever URGENTLY needed to start a machine, and you knew it was safe to do so, the average shop gremlin could always break the tag and start it since they're normally made of craptacular plastic or thin sheet metal... but it's easily enough friction to make you rethink what you're doing. Never known anyone that's ever had to break a tag like that. [0] https://en.wikipedia.org/wiki/Lockout%E2%80%93tagout https://en.wikipedia.org/wiki/Lockout%E2%80%93tagout
- donut 8mo agoSometimes a pop-up appears that I blindly accept because I happen to be typing something with spaces. Wish that button was protected somehow.
- kqr 8mo agoSuch pop-ups should never automatically get focused. The increase of them was why I switched away from Windows many years ago, and why I like to root my Android devices. It baffles me that focus-stealing notifications cannot be turned off in most OEM Androids.
- csullivannet 8mo agoI think with power tools on Windows 11 at least it forces the privilege escalation window to pop under.
- buf 8mo agoFun random fact, Eventbrite was first a security company called Molly Guard. I spent years cleaning out the 'mg-' prefixes from the code.
- davidshepherd7 8mo agoThat page is copied verbatim from https://unsung.aresluna.org/molly-guard-in-reverse/ https://unsung.aresluna.org/molly-guard-in-reverse/ (which is linked at the top). The original page also has much better formatting.
- batisteo 8mo ago…and Google-hosted.
- bookofjoe 8mo agoSorry about that. Typepad, which hosted my original blog since August 24, 2004, on September 1, 2025 gave me 30 days notice that it would shut down at midnight September 30, 2025, making my roughly 40,000 (not a typo) past posts inaccessible. I spent a frantic month trying about 10 blog hosts seeking one I, a card-carrying Technodolt, could actually use without a lot of pain. The only one that came close was Google's Blogger. Alas, it's horrible: janky, confusing, and always changing something I thought I'd finalized. Oh well...
- clbrmbr 8mo ago@dang Can a moderator update the link? The original is much better and we shouldn’t promote the copyposter.
- bookofjoe 8mo agoFull disclosure: I posted the original and it disappeared from HN so fast it made my head spin. Isn't it better that someone gave it a second chance, even if only by clicking a link?
- albedoa 8mo agoNo, your behavior is weird and hostile actually. Does Marcin even know that you lifted the content? A traditional link blog would highlight a short excerpt so that the reader might be encouraged to click through to the full piece.
- wibbily 8mo agoFun: the “Molly” in question is Ed Krol’s daughter - he’s the guy who wrote the Whole Internet User’s Guide and Catalog. https://en.wikipedia.org/wiki/Ed_Krol https://en.wikipedia.org/wiki/Ed_Krol
- AnimalMuppet 8mo agoI was almost that kid. My dad worked for Sperry Univac. For a while he was working on a ground-support trailer for the Sergeant surface-to-surface missile. He went in to work one Saturday for some kind of a major test. For some reason, he brought my mother and I along (maybe to give my mom a break). So this four-year-old (yours truly) goes into the trailer, and sees this bright red button... It was not the launch button. It was the emergency shutdown button, which would have cost them an hour to bring the trailer back online. Someone stopped me before I actually pushed it, but still, this did not make me popular. What I remember from that day is actually the parking lot, because I spent far more time in the parking lot than in the trailer.
- canucker2016 8mo agoThe wikipedia entry lists a reference explaining the history of mollyguard, along with a pic of Ed and little Molly, but an HN comment has the relevant text excerpt. see https://news.ycombinator.com/item?id=26633835 https://news.ycombinator.com/item?id=26633835
- bookofjoe 8mo agoOMG I ordered this book the second I saw your comment. It came out in 1992 and today is the first I've ever heard of it.
- meelford 8mo agoI personally know a guy who shut down an oil factory by pressing the molly guard button, just because the button looked interesting.
- deleted 8mo ago[deleted]
- TiredOfLife 8mo agoDoes the disk drive or sim card slot ejector really qualify as Molly Guard?
- pocksuppet 8mo agoThe guard is it being a tiny hole you have to find a tool to reach into, instead of a button.
- RadiozRadioz 8mo ago> There is no worse feeling for a programmer than waking up, walking up to the machine that was supposed to work through the night, and seeing it did absolutely nothing, stupidly waiting for hours for a response to a question that didn't even matter. No, there's one worse feeling. Walking up to the machine that was supposed to work throughout the night, and seeing it had a surprise update that rebooted the system. One of my favorite things about ditching Windows.
- bityard 8mo agoThis is no longer just a Windows feature. The same thing happened to me the other day on MacOS. They recently shipped a "background" update to fix a security issue and it quite unceremoniously rebooted the machine to apply the update.
- clbrmbr 8mo agoI once was a communications contractor for the major NJ power utility. One of their long time field techs (let’s just refer to him as Mr. T) was giving a tour of a substation that was built from the looks of it in the 50s. I have, you see, this bad habit of leaning on things… well Mr. T, without missing a beat, slid his forearm between my hip and a faded green Bakelite knob, the kind that goes in and out rather than twisting. He informed me that if I had leaned any further I would have shut off half of Newark.
- 6031769 8mo agoCertainly sounds like he pitied the fool. (sorry)
- stevage 8mo agoI feel like modern tv remotes are the opposite of this principle. It is often the case that almost every single button will when pushed in some way interrupt the current program, often jumping out to a different menu or changing to a different program or something. It makes handling the remote or trying to change the volume a fraught experience.
- bookofjoe 8mo agoOMG you hit my third rail when it comes to the brain-dead-designed Apple TV remote. After using one for many years I STILL press the wrong button many times every day, and in the dark, since the buttons are NOT backlit, I routinely press an unintended button. I think the user interface designer was promoted to create the Vision Pro UI/UX which is even more dreadful.
- pseudohadamard 8mo agoThis is why I have a drawer full of antipattern design remotes (which is almost all of them really except perhaps LG Magic), and use a Logitech Harmony instead. Worst remote I've ever seen was a Sony, just a solid grid of tiny rubber squares with functionality arranged apparently at random, this sort of thing: https://i.ebayimg.com/images/g/574AAOSwevZalUBY/s-l1600.jpg https://i.ebayimg.com/images/g/574AAOSwevZalUBY/s-l1600.jpg. Note the grey mode switch which changes the function of a lot of the controls. It was like Sony's engineers had an internal competition to design the most unusable remote in the industry.
- canucker2016 8mo agoSamsung learned about molly guards the hard way - recall of millions of products after accidental fires from people/pets activating the front-panel dials. see https://arstechnica.com/tech-policy/2024/08/samsung-recalls-1-1m-electric-stoves-after-fires-caused-injuries-killed-pets/ https://arstechnica.com/tech-policy/2024/08/samsung-recalls-... Luckily, there’s an easy solution recently devised that can prevent this safety hazard in homes across America, Samsung said. Customers concerned about unintentional activations can request free knob locks and covers that Samsung confirmed made it much harder to accidentally turn on the stove. During the meeting, the CPSC shared data showing that across 338 incidents between January 1, 2018, and May 30, 2024, stoves from “ten specific manufacturers” were involved in fires causing 31 injuries and two deaths. Additionally, the CPSC had recorded “two other fatal incidents where a range was accidentally turned on when a knob was bumped, but the manufacturer is unknown.” ...Companies said the CPSC data would help them “fully understand the issues” and “make sure that reasonable and foreseeable circumstances would be addressed” without impacting compliance with the Americans with Disabilities Act. After mentioning this article to relatives, one said they had nixed buying one product because of the front dials. Then we heard from a relative in another city who bought a house due to a newborn baby - one of the additional purchases was a oven/stove/range with front panel dials.
- 9dev 8mo agoThat's wild. In Europe, we generally only have front-facing dials, but either they have a built-in push to recess function, or they require some force to turn from their off position, and for the most part heat and mode are also two separate knobs where you'd need to turn both to engage. I never heard of any related injuries over here.
- pseudohadamard 8mo agoGas stoves in particular, or at least all the ones I've used, have push-to-turn on the knobs so you can't start the gas flow by bumping them, and that includes non-auto-ignite ones where the push isn't used to trigger the igniter.
- ogogmad 8mo agoThis sounded at first like a mouth guard, to stop teeth grinding.
- cynicalsecurity 8mo ago"Reverse Molly guard" is dead man's switch.
- BubbleRings 8mo agoSomebody make a keyboard where every key is a molly guard, where only one will open at a time, then make a fun video about it. And credit me for this stupid idea. Even though it wasn’t my idea.
- 1970-01-01 8mo agoSee also: https://blog.nuclearsecrecy.com/2013/09/27/final-switch-goldsboro-1961/ https://blog.nuclearsecrecy.com/2013/09/27/final-switch-gold...
- jeremyw 8mo agoLest anyone think it's just little kids that are mesmerized by the shiny red button; we were showing a potential graduate student around the compsci labs, and he walks over to an important server and simply turns it off. He could never quite explain his impulse to do so.
- vietyork 8mo agoi love the name MOLLY!