6 ms·

You Too Could Have Made Curl

143 points by sebg 2y ago

mschuster91 2y ago
> Several people eventually got involved, things were rebooted multiple times, cables were yanked and replugged in again. First after I installed arandr and forced-updated the resolution of my HDMI output to 1920×1080 the projector would suddenly show my presentation. (Later on I was told that people had the same problem in this room the day before…) That's why it is a good idea if you're a presenter to always have a Decimator [1] or its cheaper and less-capable alternative from BMD [2] in your pocket. No matter what, both of them will make sure you can get at least a signal to any sink with an HDMI or SDI port. Even 20 years after EDID, negotiation issues reign supreme... Personally, when I'm responsible for inhouse conferences, I always have the venue place a Decimator at the presenter desk and run the cable to the projector using SDI - particularly MacBooks and their USB-C dongles tend to have issues with cable lengths above 5-10 meters, I'd guess too low voltage swing. I literally never ran into incompatibility issues with this setup, only issue I had was some dumbass thinking they could unplug the Decimator to charge their phone. Additionally, SDI makes it very easy to install a split-off run to a central recording site, even if it's 100 meters of cable run away, or a split screen at the presenter's feet. No negotiation issues, everything Just F...ing Works. [1] https://decimator.com/Products/MiniConverters/12G-CROSS/12G-CROSS.html https://decimator.com/Products/MiniConverters/12G-CROSS/12G-... [2] https://www.blackmagicdesign.com/de/products/miniconverters/techspecs/W-CONM-28 https://www.blackmagicdesign.com/de/products/miniconverters/...
- lqet 2y ago
  Interesting, what exactly does the Decimator do? (Side note: I don't think it is a particularly clever idea of Decimator Design to fill their logo and homepage with images of large spiders. They are effectively eliminating around 10% of the population with arachnophobia as customers, and are making the experience of visiting their website slightly uncomfortable for large parts of the remaining population.)
  - draw_down 2y ago
    [dead]
  - mschuster91 2y ago
    > Interesting, what exactly does the Decimator do? A multitude of things, depending on how you configure it: - signal boosting of low-voltage or otherwise problematic HDMI or SDI signals, including reclocking. That's imposing virtually no latency and if you're running in a TV broadcast environment with centralized clocking it makes work easier for the downstream mixer. Primarily, it avoids issues with mis-designed sources such as cheap-ass adapter dongles that have signal integrity issues - as long as it's "good enough" for the Decimator to recognize it will output a clean and high-strength signal. - format conversion from HDMI/DVI to SDI and vice versa. That imposes a tiny bit of latency and allows the usage of "consumer" equipment with broadcast equipment, or if you use two Decimators linked by SDI, you can "just" go for far longer cable runs than you could ever do with HDMI - up to 100m, in practice way more. - up and downscaling as well as framerate conversions. This is where things really get interesting - no matter what kind of source and sink you use or what their limitations are, the scaler engine can make them talk. That includes color space conversions and bandwidth as well, and it's particularly useful if you, say, have a 12G SDI link from the source to the sink, and you want to use an older display for additional monitoring. Splice a Decimator in there and it will output the full quality signal on one output while providing a scaled-down signal on the second output.
  - wruza 2y ago
    Yeah, that’s the perfect case of a good product overrun by a questionable design idea. And its name sounds 13yo too, tbh.
  - deleted 2y ago
    [deleted]
  - Scaevolus 2y ago
    Decimator Design excluding 10% of the population is a historically accurate decimation.
- anthonyeden 2y ago
  I agree. I personally leave my Decimator MD-HX’s in ‘Free Run’ scaling mode at my preferred resolution. The in-built ‘no signal colour’ of my choosing helps me troubleshoot the problem in a signal chain quickly. Worth mentioning for the novices that SDI does not do HDCP, so you can’t pass copy-protected content via this setup without workarounds. Of course, it really should be up to the conference AV suppliers to organise all this, not the presenters themselves.
  - mschuster91 2y ago
    > Worth mentioning for the novices that SDI does not do HDCP, so you can’t pass copy-protected content via this setup without workarounds. Well, the workaround is a 10$ HDCP stripper from ebay. Easy enough. (And I think that both Decimators and BMD converters also strip HDCP, but don't quote me on that) > Of course, it really should be up to the conference AV suppliers to organise all this, not the presenters themselves. Well, conference setups tend to be a hit and miss IME. Some where the venue and the conference is run by dedicated professionals, you don't even have to tell them to place Decimators and SDI cable runs, they'll come in with these from the start in their offer... but a lot of smaller venues and conferences (especially those ran by volunteers / NGOs) don't have that knowledge and just place some random home cinema projector together with a 20 meter HDMI cable. Corporate offices are just as bad IME, I've never seen a corp conference room with anything but HDMI or, in the worst cases, VGA. Corporate just doesn't give a flying fuck unless they got a dedicated team and a proper budget working on conference room setups...
- stephen_g 2y ago
  Yes, SDI was just designed for this kind of thing (moving video long distances between cameras in studios, tape decks and patch bays in technical rooms, vision switches and capture equipment in editing bays, etc.), whereas HDMI was only ever designed for connections of a few metres (and then active optical cables had to be made to try and fix the mess)…
- Arelius 2y ago
  It looks like the MD-HX is what you want for this use case? I do a bunch of international travel, and the HD-LX seems ideal sized, but it seems like it doesn't do most of the useful functions?
  - mschuster91 2y ago
    It's "only" 3G-SDI so FullHD only.
kunley 2y ago
[flagged]
- Insanity 2y ago
  What does it matter?
  - wruza 2y ago
    Probably a part of I-never-play-games cult. Seems to mean something for them.
    - kunley 2y ago
      [flagged]
      - dijit 2y ago
        > Be kind. Don't be snarky. Converse curiously; don't cross-examine. Edit out swipes. https://news.ycombinator.com/newsguidelines.html https://news.ycombinator.com/newsguidelines.html
        kunley 2y ago
        I can comply if the same rule is applied to the passive-aggresive cult remark above. But if it's not, I say no to double standards. In fact, my original remark didn't (yet) revealed much details and reasoning about my view on gaming, but of course it suggested that it's quite a topic. I would expect that it could be an introduction to a civilized talk about the topic - while accusing me of being in a cult is certainly not. That's why also I said the guy was triggered. If he was not, the correct reply to my remark, even if he disagreed with the premise, would be sth like "what do you mean"
        wruza 2y ago
        I apologize and s/cult/club/. That said, I comment as I feel reasonable and don’t try to meet expectations on conversation structure that much. You never replied to anyone itt who did, despite them never mentioning anything remotely aggressive.
deleted 2y ago
[deleted]
trustno2 2y ago
It seems like getting projectors to run is really the hardest problem in computer science.
- Maken 2y ago
  Harder than getting printers to print?
  - mschuster91 2y ago
    At least printers give you some sort of error message. EDID negotiation or signal integrity issues in HDMI, good luck diagnosing actual causes without highly specialized (and expensive...) equipment.
    - npongratz 2y ago
      > At least printers give you some sort of error message. Inscrutable, and infamous, though they may be: https://en.wikipedia.org/wiki/PC_LOAD_LETTER https://en.wikipedia.org/wiki/PC_LOAD_LETTER
  - trustno2 2y ago
    Hey that's what we get CUPS auto-discovery for.
    - Propelloni 2y ago
      Good one!
  - high_na_euv 2y ago
    It is unreal how tech as mature as printers is so fucking unreliable
    - makeitdouble 2y ago
      Arguably it still hasn't matured yet. Or at least it's nowhere near to be a solved problem and we'll probably sidestep it before ever coming up with a real solution. I'd put it in the same bucket as TODO lists. After centuries we're still not set.
hodgesrm 2y ago
I saw this talk in person. It was delightful. My favorite part was the stories of helping random people who contacted him to help fix things like car electronics. They found his email from the OSS license acknowledgments, which apparently are accessible to ordinary users. (As they should be.)
- oefrha 2y ago
  Well he also got "I will slaughter you" through the exposure of his email in OSS license acknowledgements, so it's not always fun after all. https://daniel.haxx.se/blog/2021/02/19/i-will-slaughter-you/ https://daniel.haxx.se/blog/2021/02/19/i-will-slaughter-you/
  - tivert 2y ago
    After reading that I thought the guy who sent that email must have been crazy, and it turns out he was: https://daniel.haxx.se/blog/2021/08/09/nocais-apology/ https://daniel.haxx.se/blog/2021/08/09/nocais-apology/: > I had to retire from my career do to schizophrenia. Again, I should have not let my delusions go to the point they did nor should I have acted the way it does. My illness doesn’t detract from the rashness of my actions. There a lot of technical word salad there, like "When I say hacked, I lost every device. They rooted my charge arbitrator, I was bios bonded and I basically lost every document and all my software."
- wslh 2y ago
  [flagged]
silvestrov 2y ago
The problem is not to make a tool like curl. The problem is the marketing and getting people to use it. You can easily make the best product and still not being able to get the word out there.
- tootie 2y ago
  There was a bit of PR "war" between curl and wget a long time ago. At some point curl just became everyone's goto and even the reference implementation for http.
  - taneq 2y ago
    I never did really figure out why curl became a thing when we’d been wget to do that since 2001.
    - senko 2y ago
      Because MacOS included curl because wget is GPL: https://daniel.haxx.se/blog/2021/09/25/curls-first-twenty-years-on-the-mac/ https://daniel.haxx.se/blog/2021/09/25/curls-first-twenty-ye...
    - yetihehe 2y ago
      Because you could use curl as a library in PHP and some other languages.
    - bityard 2y ago
      They're actually very different tools: wget is mostly useful only for downloading of web resources, curl is for making arbitrary requests.
  - masto 2y ago
    Many moons ago, I was in the small ISP business, and I discovered the aftermath of an attempted script kiddie hack on one of our servers. When I examined the logs I realized we were extremely vulnerable to the remote code execution exploit but had been completely saved by two things: they kept trying to use curl to install the payload, but we only had wget installed; and their scripts were extremely Linux-centric but we were using FreeBSD.
tempfile 2y ago
arandr mentioned! I use it all the time. Never had an issue.
- password4321 2y ago
  TIL: ARandR is a tool to control output positioning and properties of multiple monitors using XRandR. https://christian.amsuess.com/tools/arandr/ https://christian.amsuess.com/tools/arandr/ Recently set up something similar for Windows as a win in the battle against time wasted thanks to auto-logout. https://github.com/caoyue/WindowResizer https://github.com/caoyue/WindowResizer
- yjftsjthsd-h 2y ago
  ... Having used arandr for ~forever, it suddenly occurs to me that people complaining about display issues on Linux maybe just don't know it exists? That would explain a bit
ketanmaheshwari 2y ago
"Very few things are an immediate success". Wise words.
jeanlucas 2y ago
Daniel is a unique OSS builder. We asked him to give a talk to our community and he accepted, no questions asked, just showed up :-) His commitment to spread the word of curl and OSS is really admirable.
shark1 2y ago
The man built a software used by billions and still gets nervous talking in public :) It was a delightful presentation.

143 points by sebg 2y ago

> Several people eventually got involved, things were rebooted multiple times, cables were yanked and replugged in again. First after I installed arandr and forced-updated the resolution of my HDMI output to 1920×1080 the projector would suddenly show my presentation. (Later on I was told that people had the same problem in this room the day before…) That's why it is a good idea if you're a presenter to always have a Decimator [1] or its cheaper and less-capable alternative from BMD [2] in your pocket. No matter what, both of them will make sure you can get at least a signal to any sink with an HDMI or SDI port. Even 20 years after EDID, negotiation issues reign supreme... Personally, when I'm responsible for inhouse conferences, I always have the venue place a Decimator at the presenter desk and run the cable to the projector using SDI - particularly MacBooks and their USB-C dongles tend to have issues with cable lengths above 5-10 meters, I'd guess too low voltage swing. I literally never ran into incompatibility issues with this setup, only issue I had was some dumbass thinking they could unplug the Decimator to charge their phone. Additionally, SDI makes it very easy to install a split-off run to a central recording site, even if it's 100 meters of cable run away, or a split screen at the presenter's feet. No negotiation issues, everything Just F...ing Works. [1] https://decimator.com/Products/MiniConverters/12G-CROSS/12G-CROSS.html https://decimator.com/Products/MiniConverters/12G-CROSS/12G-... [2] https://www.blackmagicdesign.com/de/products/miniconverters/techspecs/W-CONM-28 https://www.blackmagicdesign.com/de/products/miniconverters/...

lqet 2y ago
Interesting, what exactly does the Decimator do? (Side note: I don't think it is a particularly clever idea of Decimator Design to fill their logo and homepage with images of large spiders. They are effectively eliminating around 10% of the population with arachnophobia as customers, and are making the experience of visiting their website slightly uncomfortable for large parts of the remaining population.)
- draw_down 2y ago
  [dead]
- mschuster91 2y ago
  > Interesting, what exactly does the Decimator do? A multitude of things, depending on how you configure it: - signal boosting of low-voltage or otherwise problematic HDMI or SDI signals, including reclocking. That's imposing virtually no latency and if you're running in a TV broadcast environment with centralized clocking it makes work easier for the downstream mixer. Primarily, it avoids issues with mis-designed sources such as cheap-ass adapter dongles that have signal integrity issues - as long as it's "good enough" for the Decimator to recognize it will output a clean and high-strength signal. - format conversion from HDMI/DVI to SDI and vice versa. That imposes a tiny bit of latency and allows the usage of "consumer" equipment with broadcast equipment, or if you use two Decimators linked by SDI, you can "just" go for far longer cable runs than you could ever do with HDMI - up to 100m, in practice way more. - up and downscaling as well as framerate conversions. This is where things really get interesting - no matter what kind of source and sink you use or what their limitations are, the scaler engine can make them talk. That includes color space conversions and bandwidth as well, and it's particularly useful if you, say, have a 12G SDI link from the source to the sink, and you want to use an older display for additional monitoring. Splice a Decimator in there and it will output the full quality signal on one output while providing a scaled-down signal on the second output.
- wruza 2y ago
  Yeah, that’s the perfect case of a good product overrun by a questionable design idea. And its name sounds 13yo too, tbh.
- deleted 2y ago
  [deleted]
- Scaevolus 2y ago
  Decimator Design excluding 10% of the population is a historically accurate decimation.
anthonyeden 2y ago
I agree. I personally leave my Decimator MD-HX’s in ‘Free Run’ scaling mode at my preferred resolution. The in-built ‘no signal colour’ of my choosing helps me troubleshoot the problem in a signal chain quickly. Worth mentioning for the novices that SDI does not do HDCP, so you can’t pass copy-protected content via this setup without workarounds. Of course, it really should be up to the conference AV suppliers to organise all this, not the presenters themselves.
- mschuster91 2y ago
  > Worth mentioning for the novices that SDI does not do HDCP, so you can’t pass copy-protected content via this setup without workarounds. Well, the workaround is a 10$ HDCP stripper from ebay. Easy enough. (And I think that both Decimators and BMD converters also strip HDCP, but don't quote me on that) > Of course, it really should be up to the conference AV suppliers to organise all this, not the presenters themselves. Well, conference setups tend to be a hit and miss IME. Some where the venue and the conference is run by dedicated professionals, you don't even have to tell them to place Decimators and SDI cable runs, they'll come in with these from the start in their offer... but a lot of smaller venues and conferences (especially those ran by volunteers / NGOs) don't have that knowledge and just place some random home cinema projector together with a 20 meter HDMI cable. Corporate offices are just as bad IME, I've never seen a corp conference room with anything but HDMI or, in the worst cases, VGA. Corporate just doesn't give a flying fuck unless they got a dedicated team and a proper budget working on conference room setups...
stephen_g 2y ago
Yes, SDI was just designed for this kind of thing (moving video long distances between cameras in studios, tape decks and patch bays in technical rooms, vision switches and capture equipment in editing bays, etc.), whereas HDMI was only ever designed for connections of a few metres (and then active optical cables had to be made to try and fix the mess)…
Arelius 2y ago
It looks like the MD-HX is what you want for this use case? I do a bunch of international travel, and the HD-LX seems ideal sized, but it seems like it doesn't do most of the useful functions?
- mschuster91 2y ago
  It's "only" 3G-SDI so FullHD only.

kunley 2y ago

[flagged]

Insanity 2y ago
What does it matter?
- wruza 2y ago
  Probably a part of I-never-play-games cult. Seems to mean something for them.
  - kunley 2y ago
    [flagged]
    - dijit 2y ago
      > Be kind. Don't be snarky. Converse curiously; don't cross-examine. Edit out swipes. https://news.ycombinator.com/newsguidelines.html https://news.ycombinator.com/newsguidelines.html
      - kunley 2y ago
        I can comply if the same rule is applied to the passive-aggresive cult remark above. But if it's not, I say no to double standards. In fact, my original remark didn't (yet) revealed much details and reasoning about my view on gaming, but of course it suggested that it's quite a topic. I would expect that it could be an introduction to a civilized talk about the topic - while accusing me of being in a cult is certainly not. That's why also I said the guy was triggered. If he was not, the correct reply to my remark, even if he disagreed with the premise, would be sth like "what do you mean"
        wruza 2y ago
        I apologize and s/cult/club/. That said, I comment as I feel reasonable and don’t try to meet expectations on conversation structure that much. You never replied to anyone itt who did, despite them never mentioning anything remotely aggressive.

deleted 2y ago

[deleted]

trustno2 2y ago

It seems like getting projectors to run is really the hardest problem in computer science.

Maken 2y ago
Harder than getting printers to print?
- mschuster91 2y ago
  At least printers give you some sort of error message. EDID negotiation or signal integrity issues in HDMI, good luck diagnosing actual causes without highly specialized (and expensive...) equipment.
  - npongratz 2y ago
    > At least printers give you some sort of error message. Inscrutable, and infamous, though they may be: https://en.wikipedia.org/wiki/PC_LOAD_LETTER https://en.wikipedia.org/wiki/PC_LOAD_LETTER
- trustno2 2y ago
  Hey that's what we get CUPS auto-discovery for.
  - Propelloni 2y ago
    Good one!
- high_na_euv 2y ago
  It is unreal how tech as mature as printers is so fucking unreliable
  - makeitdouble 2y ago
    Arguably it still hasn't matured yet. Or at least it's nowhere near to be a solved problem and we'll probably sidestep it before ever coming up with a real solution. I'd put it in the same bucket as TODO lists. After centuries we're still not set.

hodgesrm 2y ago

I saw this talk in person. It was delightful. My favorite part was the stories of helping random people who contacted him to help fix things like car electronics. They found his email from the OSS license acknowledgments, which apparently are accessible to ordinary users. (As they should be.)

oefrha 2y ago
Well he also got "I will slaughter you" through the exposure of his email in OSS license acknowledgements, so it's not always fun after all. https://daniel.haxx.se/blog/2021/02/19/i-will-slaughter-you/ https://daniel.haxx.se/blog/2021/02/19/i-will-slaughter-you/
- tivert 2y ago
  After reading that I thought the guy who sent that email must have been crazy, and it turns out he was: https://daniel.haxx.se/blog/2021/08/09/nocais-apology/ https://daniel.haxx.se/blog/2021/08/09/nocais-apology/: > I had to retire from my career do to schizophrenia. Again, I should have not let my delusions go to the point they did nor should I have acted the way it does. My illness doesn’t detract from the rashness of my actions. There a lot of technical word salad there, like "When I say hacked, I lost every device. They rooted my charge arbitrator, I was bios bonded and I basically lost every document and all my software."
wslh 2y ago
[flagged]

silvestrov 2y ago

The problem is not to make a tool like curl. The problem is the marketing and getting people to use it. You can easily make the best product and still not being able to get the word out there.

tootie 2y ago
There was a bit of PR "war" between curl and wget a long time ago. At some point curl just became everyone's goto and even the reference implementation for http.
- taneq 2y ago
  I never did really figure out why curl became a thing when we’d been wget to do that since 2001.
  - senko 2y ago
    Because MacOS included curl because wget is GPL: https://daniel.haxx.se/blog/2021/09/25/curls-first-twenty-years-on-the-mac/ https://daniel.haxx.se/blog/2021/09/25/curls-first-twenty-ye...
  - yetihehe 2y ago
    Because you could use curl as a library in PHP and some other languages.
  - bityard 2y ago
    They're actually very different tools: wget is mostly useful only for downloading of web resources, curl is for making arbitrary requests.
- masto 2y ago
  Many moons ago, I was in the small ISP business, and I discovered the aftermath of an attempted script kiddie hack on one of our servers. When I examined the logs I realized we were extremely vulnerable to the remote code execution exploit but had been completely saved by two things: they kept trying to use curl to install the payload, but we only had wget installed; and their scripts were extremely Linux-centric but we were using FreeBSD.

tempfile 2y ago

arandr mentioned! I use it all the time. Never had an issue.

password4321 2y ago
TIL: ARandR is a tool to control output positioning and properties of multiple monitors using XRandR. https://christian.amsuess.com/tools/arandr/ https://christian.amsuess.com/tools/arandr/ Recently set up something similar for Windows as a win in the battle against time wasted thanks to auto-logout. https://github.com/caoyue/WindowResizer https://github.com/caoyue/WindowResizer
yjftsjthsd-h 2y ago
... Having used arandr for ~forever, it suddenly occurs to me that people complaining about display issues on Linux maybe just don't know it exists? That would explain a bit

ketanmaheshwari 2y ago

"Very few things are an immediate success". Wise words.

jeanlucas 2y ago

Daniel is a unique OSS builder. We asked him to give a talk to our community and he accepted, no questions asked, just showed up :-) His commitment to spread the word of curl and OSS is really admirable.

shark1 2y ago

The man built a software used by billions and still gets nervous talking in public :) It was a delightful presentation.