Re: (fwd) [FD] OpenBSD kernel relinking is not transactional and a local exploit exists
On Mon, Jun 19, 2023 at 05:34:12PM -0600, Theo de Raadt wrote: > That writeup is bullshit. Ok, I see. -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
(fwd) [FD] OpenBSD kernel relinking is not transactional and a local exploit exists
This happened in my mailbox today. FD means "full disclosure" and is publicly available mailing list. I repost onto misc because if this is a real cat, seems it is out of the bag already. Other than being subscribed to FD, I have no connection. - Forwarded message from "Schech, C. W. (\"Connor\")" - Date: Sat, 17 Jun 2023 09:40:16 + From: "Schech, C. W. (Connor)" To: fulldisclos...@seclists.org Subject: [FD] OpenBSD kernel relinking is not transactional and a local exploit exists The automatic and mandatory-by-default reordering of OpenBSD kernels is NOT transactional and as a result, a local unpatched exploit exists which allows tampering or replacement of the kernel. Arbitrary build artifacts are cyclically relinked with no data integrity or provenance being maintained or verified for the objects being consumed with respect to the running kernel before and during the execution of the mandatory kernel_reorder process in the supplied /etc/rc and /usr/libexec scripts. The reordering occurs at the end of installation process and also automatically every reboot cycle thereafter unless manually bypassed by a knowledgable party. The kernel_reorder routine verifies a SHA256 signature for the linked kernel from last boot but does not verify the integrity or provenance of any objects kept in the kernel "link kit" installed in /usr/share/relink, so arbitrary objects can be injected and automatically relinked at the next startup. I have verified that it is indeed the case that both valid kernels with a different uname and kernels which cause data destruction due to over-tuning of a subset of the components which were compiled manually and copied into /usr/share/relink and crash the system after being booted once relinked but which do not match the build of the running kernel at the time they were copied into /usr/share/relink as working proof-of-concept exploits. Install media are also open to tampering and exploitation as signed checksum data are not carried with the install sets inside the installation image and an improperly-encapsulated poorly-documented tarball of unverifiable (in the sense of SLSA) kernel objects is embedded in the base distribution and then relinked with a new random ordering of the objects cyclically between boot cycles. Sites with a strong security posture are advised that this is a critical vulnerability and likely deliberate back door into the system. Additionally, OpenBSD leaks the state of the pseudorandom number generator to predictable locations on disk and in system memory at a fixed point during every start up and shutdown procedure. The lack of build process hardening has been on-going for over three years. Theo de Raadt is disinterested in improving or reviewing the design or providing any further clarification, as he has stated on the mailing list when shortfalls in the relinking process were reported over the past ~3 years. I hope that this can come to the attention of a third-party technical expert with standing in the computer security industry. Workaround: As the link kit is embedded in the base distribution and automatically relinked without an option to disable it in the provided installation script it requires manual removal at present. Cf. https://marc.info/?l=openbsd-bugs=159074964523007=2 (noted lack of idempotency) https://marc.info/?l=openbsd-bugs=168688579123005=2 (noted lack of integrity or provenance verification and the consumption of invalid objects) https://slsa.dev/spec/v1.0/levels#build-l2-hosted-build-platform: "Track/Level Requirements Focus Build L3 Hardened build platform Tampering during the build" ___ Sent through the Full Disclosure mailing list https://nmap.org/mailman/listinfo/fulldisclosure Web Archives & RSS: https://seclists.org/fulldisclosure/ - End forwarded message -
Re: tracker-miner-fs-3
On Sun, Feb 19, 2023 at 06:09:55AM +0100, Daniele B. wrote: > Feb 19, 2023 03:49:45 Tomasz Rola : > [...] > > I ended up uninstalling it however thanks for this command too, interesting. Yep. I admit I am unceremonial when dealing with my own systems. And I am not sure if I would follow my own advices if I was not me. > (Hint to read the rest of my reply: I'm always in the need to mind, use or > project > myself *effective* gui despite the context. Thats my second job! ) > > > Install Midnight Commander, perhaps? Warning: it does not have [...] > Thanks for the charm of gem, indeed.. :D > > > > > I also like dired-mode in Emacs, but for this to work, one has to like > > Emacs. Actually, one has to love Emacs. "Like" is not enough in this > > case. > > Difficult to evaluate and comment on a *big stuff* like Emacs. [...] > > Summarizing again: I'm not in the need of Emacs (I'm focus on the > web since years) and I think fortunately is so. As of MC being a gem, it did not come to my mind until writing of my previous email, but, yes, it worked for so many years and I do not recall it failing me even once. Discs, operating systems, unicode in filenames, it keeps to "just working". Emacs, while much more complicated, is in different league - it is an alien artefact standing in the middle of a cornfield. I think most people simply pretend it is not there. Very few really need Emacs, which is good, I think. I sometimes - very rarely - use graphical file managers. They seem too slow. But if they do the job, fine. As a side note, since we speak about file management, I also often do things with files from command line. Not very long ago I did it to about 17 thousand small files scattered in few dirs. I had to write a shell script and test quite a bit, because error was not good idea. But if you plan to do complex procedures with files, writing a script/program can help a lot. Also, doing not so complex procedures, but when one is afraid to make a mistake. I am sometimes only half-awaken, so writing commands in that state of mind is risky. A script, sometimes a Makefile, run it when I am in hurry, so the computer (who never gets nervous) takes this off me. > Indeed, my best advice about gui is that any good stuff should be > concieved simple enough to result effective to user. > > I want also to thank you for the time of your post. I got the lucky > chance to read you monitoring the fever of my daughter. And sorry > for the off-topic commenting style. Oh. I hope your daughter is going to be ok. Keep smiling. -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: tracker-miner-fs-3
On Thu, Feb 16, 2023 at 07:13:50PM +0100, Daniele B. wrote: > Thanks David, thanks Mike. > > In the meanwhile I also investigated a little bit.. > By memory (my case) is the following, I'm with Thunar on XFCE (without gnome > services): > > tracker3-miner depends on nautilus > nautilus depends on file-roller > file-roller depends on thunar-archive-plugin (omg.. optional) > > Indeed connecting everything something nasty to think about, this tracker.. > > What is your best advise? Am a bit late but in case of doubt: chmod a-x `which tracker-miner-fs-3` && ls -axl `which tracker-miner-fs-3` and see if you are good during next few days. Yes -> leave it like that, chmodded. Sure, some part of your desktop may seem a little bit unusable. OTOH, maybe it is redundant and one can live without it? Install Midnight Commander, perhaps? Warning: it does not have trashcan, so there is no "undo" (unless something changed during last twenty years). On the plus side: optionally works in vt100 mode (only one option to choose from), does not display unnecessary icons. Big plus: I am rather sure it will work with Gnome 15, still like a charm, always like a charm (if you ask me - a real gem of a software). I also like dired-mode in Emacs, but for this to work, one has to like Emacs. Actually, one has to love Emacs. "Like" is not enough in this case. -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: Configure OpenBSD for remote server rarely used
On Sun, Nov 27, 2022 at 09:37:19AM +, James Johnson wrote: > Hi all, > > OpenBSD is amazing. But I need help in configuring it correctly as a > remote server, rarely used. > > > The main thing I am trying to do is to make it sleep every now and > then to protect resources. I am very flexible on how to do this, but > have been unable to do so. > Here's what I tried : [...] So to sum up your requirements, you want a self driving box which waits, and once every month or six wakes up, does something, then goes idle again. I would avoid power down/up completely - boot takes time, and fsck takes some more time. Also, AFAIK electronics wears down every time it goes on-off. Modern HDD are said to live to 5 on-off cycles, so assume 2 cold boots. But random things can happen, because on-off means power spike. If you have no problem with eletricity, I would keep it going all the time. I would however minimise writes. Work on temporary data in ramdisk, write results to disk. Something like this. BIOS battery goes down faster when computer is powered down. When it is up, clock gets power from the wall and saves the battery. I assume the modern CMOS battery will only keep the clock for about a year without power and it will not recharge when you power up. After that time (and before that time, too, but less necessary), every boot should include query to time server and adjusting the hardware clock. I would buy a decent PSU. Last time I wanted to know, Seasonic was the maker of best ones a mortal could buy. Their last unit I bought came with 10 years warranty. AND, according to description, it was built with classic electronic art, analog parts, no digital. So if you are so inclined, you can ask your electronic buddy to inspect it and perhaps even replace some parts with better ones. Or repair it. If microcontroller goes bunk, you are out of luck, I assume they somehow protect their eproms. If you plan to store some long term data on this box, I would avoid SSD. They are fast but they also can go bunk and when they do, chance of recovering data is close to nil (from what I have read). I would consider putting the box in a plastic bag to protect from dust and humidity. Dust will clog into radiators, make chips go hotter, ventillators work harder. I have not tested this, however. I assume thermal exchange with loose bag over the box should go ok, but you need to test it very carefully, monitoring temps all the time - all temps. HTH -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: less prints superfluous characters with --no-init
On Mon, Nov 21, 2022 at 08:51:36AM +0100, Jan Stary wrote: > On Nov 21 01:38:41, rto...@ceti.pl wrote: > > I guess it would not be very hard to just add few more *roff hacks > > Stop right here. My horses froze hanging in the air... :-) -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: less prints superfluous characters with --no-init
On Mon, Nov 21, 2022 at 01:38:41AM +0100, Tomasz Rola wrote: [...] > I guess it would not be very hard to just add few more *roff hacks > similar to one above. Or maybe a command (shell script) to retrieve > relevant subsection from manpage and print just this one. And maybe > also list names of subsections available on the page. It seems that > '^[A-Z]( |[A-Z])+$' is the name regexp... So... Forgot to mention that woman mode in emacs gives exactly this - jumping to sections and some more. -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: less prints superfluous characters with --no-init
On Sun, Nov 20, 2022 at 08:45:01PM +, Jason McIntyre wrote: > On Sun, Nov 20, 2022 at 08:09:13PM +0100, Tomasz Rola wrote: [...] > > I am writing this from ParrotOS (Debian derivative) and since I am > > avid user of bash, I can do "man bash-builtins" and it prints me a > > very nice looking summary. Bash package version is 5.1-2+deb11u1, > > which probably means 5.1 with some Debian-specific addons. > > > > the thing is, you have to be aware of a builtins page in order to know > to type "man builtins" (or whatever). you would need to know that a > command is a builtin. but if you know it's a builtin, then you can just > type "man ksh" and get the documentation. Sure. As a matter of fact, I was for years grumbling about how long bash manpage is and how long it takes to locate relevant info. Today I have learned to look for "builtin(|s)" with apropos and here it is. I have dug a bit deeper and "zcat /usr/share/man/man7/bash-builtins.7.gz" shows me that it is just a *roff hack to display subsection of bash manpage. Worth remembering. > we could add all these commands to ksh's NAME, but that would look awful. I guess it would not be very hard to just add few more *roff hacks similar to one above. Or maybe a command (shell script) to retrieve relevant subsection from manpage and print just this one. And maybe also list names of subsections available on the page. It seems that '^[A-Z]( |[A-Z])+$' is the name regexp... So... $ man bash | grep -iE '^[A-Z]( |[A-Z])+$' NAME SYNOPSIS COPYRIGHT DESCRIPTION ... SHELL BUILTIN COMMANDS ... and so on. -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: less prints superfluous characters with --no-init
On Sun, Nov 20, 2022 at 01:32:54PM -, Christian Weisgerber wrote: > On 2022-11-20, Reuben mac Saoidhea wrote: > > >> It is a builtin, so it is documented inside ksh. > > > > i think the 4.3BSD manual allowed for example `man while' for `man sh'? > > FreeBSD has a builtin(1) man page that attempts to list the csh(1) > and sh(1) builtins and points to the respective man pages: > > https://www.freebsd.org/cgi/man.cgi?query=builtin > > It's an attempt to do something about this problem, but I think the > result isn't that great. I am writing this from ParrotOS (Debian derivative) and since I am avid user of bash, I can do "man bash-builtins" and it prints me a very nice looking summary. Bash package version is 5.1-2+deb11u1, which probably means 5.1 with some Debian-specific addons. -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: A minimal browser in base
On Sat, Sep 10, 2022 at 09:04:54PM +0300, unix wrote: > Hello. My reasons for this proposition: > 1. The user will be able to test basic websites without installing > anything. > 2. The user will be able to read an incredibly useful official > FAQ, with no external devices involved. > 3. The user will be able to manage mailing list > membership via the web interface. > 4. Using ftp(1) and reading pure HTML is inconvenient. > 5. The browser (Lynx) was already included. It was removed due to > concerns about code quality, licensing, and support for insecure > protocols. > You could say that you don't need a browser installed by default if you > have a network connection and can install the package anyway. > Still, am I the only one who feels like it's pretty much the only thing > missing in the base for a comfortable day to day desktop usage? > So, if we include a browser, which one? [...] > If you know about any other options, I will be interested in > discussing them. I do not want to derail the discussion but I think that if I can have a pendrive with O*BSD install, then I can also have another pendrive with some sources and maybe a bash script to compile them. For browsing on the text console, I like emacs-w3m, which (if I am correct) is w3m for rendering pages and emacs for showing them, with tabs and easy way to copy-paste fragments into other emacs buffer, be it a code or shell. I would probably also have lynx on this pendrive, because it can open gopher sites, so I can vent off some steam by looking at obsolete stuff. I realize that certain propositions are no-no for base system (and I totally agree with this), which is why my best option is to be my own guest and help myself. In my opinion none of text browsers I use nowadays (links/elinks, lynx && emacs-w3m) will work on every website (some are polite enough to tell me I need to turn js on). There is good chance with pages written for programmers, however. -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: dump(8) is slow
On Tue, Aug 09, 2022 at 07:06:04PM -0600, Theo de Raadt wrote: > Tomasz Rola wrote: > > > Ok. But what is a theoretic speed limit for this device? > > [...] > > Bravo, you tested the speed at 1024 bytes of data per system call. The OP complained his dump was slow. I was wondering if it was slow because of problem with dump, or if the device from which he was dumping was slow by itself. If he did dd from device->null and measured time, he would have basis to claim that slowness was a fault of dump - if dd was, say twice as fast. -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: dump(8) is slow
On Tue, Aug 09, 2022 at 02:21:21PM +0200, Christian Weisgerber wrote: > Moving 9TB with dump|restore from an old hard disk to a bigger one > reminded me again that dump(8) is, well, slow: > > DUMP: 9104433830 tape blocks > DUMP: Date of this level 0 dump: Sat Aug 6 16:36:52 2022 > ... > DUMP: Date this dump completed: Tue Aug 9 13:51:01 2022 > DUMP: Average transfer rate: 36530 KB/s > > That is far below the read-write speed of a modern SATA drive. > systat(1) clearly showed that the source disk and dump(8) was the > bottleneck, not the target disk and restore(8). Too much seeking? Ok. But what is a theoretic speed limit for this device? If I do something like this on my laptop w/ssd: # date +'%s'; dd if=/dev/sda2 of=/dev/null bs=1024 count=$((512*1024)); date +'%s' 1660089697 521565184 bytes (522 MB, 497 MiB) copied, 2 s, 261 MB/s 524288+0 records in 524288+0 records out 536870912 bytes (537 MB, 512 MiB) copied, 2,06702 s, 260 MB/s 1660089699 I tried it with reading first 512 megs, for you, since you want to deal with terabytes, count= would need to be adjusted, say, 100 gigs? Reasoning: the specification for sata says one thing, but it says theoretical upper speed, if I am correct. So you want to know about real speed limit of _this_ device. -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: Freeze on OpenBSD 7.1
On Mon, Jul 18, 2022 at 12:14:20AM +0200, Tobias Fiebig wrote: > Heho, > If the machine just hardlocks (no panic), and the memory seems fine > (did you run memtest?), and there are no blown elcos on the > motherboard, my first guess would be testing another PSU; The > pattern sounds familiar. > > Also, the voltages do not necessarily look overly healthy... but > that might just be a fluke. [...] > Could you help me please ? Thank you very much ! > > Nicolas, Paris. > [...] > hw.sensors.it0.volt0=4.08 VDC (VCORE_A) > hw.sensors.it0.volt1=4.08 VDC (VCORE_B) > hw.sensors.it0.volt2=4.08 VDC (+3.3V) > hw.sensors.it0.volt3=6.85 VDC (+5V) > hw.sensors.it0.volt4=16.32 VDC (+12V) > hw.sensors.it0.volt5=4.01 VDC (-12V) > hw.sensors.it0.volt6=4.05 VDC (-5V) > hw.sensors.it0.volt7=6.85 VDC (+5VSB) > hw.sensors.it0.volt8=4.08 VDC (VBAT) > What Tobias wrote - voltages look way too much off. Onboard sensors are not always trusty, so I would go with real voltmeter. If you do not feel comfortable with electrical stuff, ask somebody for help. I would: 1. turn computer off, open the case 2. find molex connector https://en.wikipedia.org/wiki/Molex_connector#Disk_drive 3. pull it out of the case so I could reach it without touching insides of the case 4. turn computer on and start memtest 5. put black probe of voltmeter into black hole of molex 6. put red probe into another hole of molex (yellow or red) and see what voltages it measures Do not touch or move any cables beyound molex while the hw is powered on. This means if you move molex cable, it should not push on other cables - because some cables are very touchy touchy, like hdd data connectors. >From what I recall, PSU voltages are good when within +- 5% of what they should be. Yours look bad, because ~30% too big. Bear in mind, I am not electrical engineer. If you do not own voltmeter, this probably means you should ask for help of someone who does. -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: www.openbsd.org unreachable for a few days
On Tue, Dec 15, 2020 at 10:55:27AM -0700, Theo de Raadt wrote: > Janne Johansson wrote: > > > Den tis 15 dec. 2020 kl 13:00 skrev Ottavio Caruso < > > ottavio2006-usenet2...@yahoo.com>: > > > > > Hi, > > > I asked on Freenode#OpenBSD and apparently it's only me, but I haven't > > > been able to access www.openbsd.org for a few days. > > > > > > $ traceroute 129.128.5.194 > > > traceroute to 129.128.5.194 (129.128.5.194), 30 hops max, 60 byte packets > > > > > > > > ... > > > > > > > 11 40ge1-3.core1.lon2.he.net (195.66.224.21) 35.068 ms > > > 100ge4-1.core1.nyc4.he.net (72.52.92.166) 101.075 ms 86.105 ms > > > > > > I heard a similar complaint elsewhere and that was going over he.net also, > > whereas I could reach it in the mean time, going over shawn to ualbert.ca > > and onwards, so I guess he.net is presently bad at routing to the correct > > places. > > Sorry, you'd be incorrect blaming he.net. > > UofA border is doing some kind of broken filtering, or perhaps it is > incorrect routing of replies into EDU network (cybera/canarie). > > It is up to them to fix it, but there have been no replies yet. I have just traced www.openbsd.org from Poland: [... skip irrelevant part ...] 4 pl-waw02a-ri1-ae-0-0.aorta.net (84.116.138.94) 12.570 ms 13.431 ms 15.473 ms 5 213.46.178.30 (213.46.178.30) 14.047 ms 15.825 ms 13.434 ms 6 100ge16-2.core1.par2.he.net (184.105.213.121) 39.736 ms 53.853 ms 41.229 ms 7 100ge11-2.core1.nyc4.he.net (72.52.92.113) 107.904 ms 116.301 ms 109.851 ms 8 100ge14-1.core1.tor1.he.net (184.105.80.10) 119.988 ms 124.484 ms 119.546 ms 9 100ge6-1.core1.ywg1.he.net (184.105.64.102) 138.756 ms 140.801 ms 139.474 ms 10 100ge5-2.core1.yxe1.he.net (184.104.192.70) 157.590 ms 153.117 ms 155.520 ms 11 100ge11-2.core1.yeg1.he.net (72.52.92.61) 154.828 ms 154.963 ms 156.100 ms 12 university-of-alberta-sms.10gigabitethernet2-2.core1.yeg1.he.net (184.105.18.50) 156.854 ms 157.227 ms 160.990 ms 13 cabcore-esqgw.corenet.ualberta.ca (129.128.255.35) 158.464 ms 163.029 ms katzcore-esqgw.corenet.ualberta.ca (129.128.255.41) 157.714 ms 14 * * * 15 gateway-5.ucs.ualberta.ca (129.128.5.1) 166.056 ms 155.914 ms 160.884 ms 16 obsd3.srv.ualberta.ca (129.128.5.194) 154.972 ms 160.039 ms 156.403 ms 2020-12-15 18:54:31 www.openbsd.org reachable HTH, -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Emulating ps/2 for usb keyboard [was Re: Mouse hotplug in X?]
On Sun, Nov 01, 2020 at 01:12:30PM -0800, obs...@loopw.com wrote: > note that ps/2 is not actually designed for hotplug (I fried a > keyboard controller to bring you this knowledge) Thanks. I kind of know about ps/2. Albeit it happened once or twice that I hotplugged ps/2 keyboard. I later vowed to avoid it. Right now it is unplugged - my old ps/2 kbs are running issues and I am not very happy about it. I notice some lagging with my current usb kb, which is the cheapest mech [1] I was able to find, so maybe this is because of the "cheap". Or, the usb part of system (still Linux) is not so fast. If gaming guys can give some clues, they seem to prefer ps/2 kbds, which probably means the lag of usb is too big to suffer. I would be happy to connect my kbd into ps/2 port one day, but a quick test (usb kbd -> usb-to-ps2 converter -> ps2-to-usb converter -> usb plughole) showed me that this one kbd cannot speak ps/2 protocol. I also tested same procedure on rubber dome usb kbd from same maker and this one connected without problem. So, now I have a problem. I would like to keep plugging my new keyboards into ps/2 hole. I really would. But for plugging the mech which I have now, I would need some special kind of usb-to-ps/2 converter. The dumb one does not work and I could not find anything better. It is obvious I will be able to buy "some" ps/2 kbd for a while. But they will be of deteriorating quality, post-office after-use sell-outs. I will probably eke out for better mech, which will last me good ten years. But, stuff breaks. And in the future there might be usb-only kbds which will not understand how to talk "ps/2-ish". So, obviously, to connect such keyboard into ps/2 hole, one would need a translator. So far, the only DIY thing I _maybe_ could pull out is RPi - it would take usb kbd into its usb port and translate characters (by C program) into five gpio ports connected to ps/2 male plug. However, using whole big RPi sounds a bit like overkill. And I am yet to learn the stuff. So, is there something I could hunt down, some kind of smarter usb-to-ps/2 converter? For now, I am just curious and try to be proactive with my hardware choices. But I will gladly learn if anybody has a clue or hint for me (oh, not just for me, there are going to be many more people like me, they just do not know yet). [1] If anybody is curious, it was supposed to be my inroad into the land of mechs. On the plus side, I love "ten key less" layout. I want more of this. On the 50-50 side, it has Outemu Blue switches. They work, but sometimes I have to press the key more than once (after about year of not very heavy typing). I have it plugged into usb hub with micro on-off switches for individual devices, so when I get annoyed, I "hard reset" the keyboard and after that it somehow comes back to the order. There is nothing on minus side yet. I expected it would not be perfect for this price but it is better than I expected. -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: Mouse hotplug in X?
On Sun, Nov 01, 2020 at 01:51:45PM -0500, Brennan Vincent wrote: > Is it possible to get hot-plugging of USB mice to work? Can't find > it in Google or man pages. My X is hardly the newest one and I can testplug usb mice at will. They work along ps/2 mouse (but just one mouse cursor/arrow, if I recall - it was a bit of time since I did it last). Same for keyboards. -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: How many IPs can I block before taking a performance hit?
On Wed, Aug 12, 2020 at 03:00:03PM +0200, Martin Sukany wrote: > Hi, > > as the tables are stored in RAM anyway during thee processing it’s > moreless matter of how fast are your DIMMs / CPU. I’m usually work > with several tables with cca 30 K records - no impact on the > performance so far. So, for as long as the table(s) do not spill out of cpu's cache, it is going to be a not so huge problem. If you run memtest, the difference between various caches is big, but cache vs ram is huge. Is there a way to have listing of offending IPs and perhaps grouping them into /nn subnets - other than writing oneself the script? Something as easy as awk might suffice, I guess - and then instead of five rules, just one rule for a subnet. If IPs are close enough to form a subnet (now, what is "close enough", there might be interesting problem). Of course, this way, some IPs will be excluded even if they did nothing wrong (yet). Another nice thing to have might be a utility which looks for rules and disables those which did not fired up during last x seconds (by looking up through firewall logs, perhaps). I have no idea if there is such utility and am not sure how to look it up. -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: Hardening browser
On Sat, Mar 07, 2020 at 11:55:59AM -0700, Luke A. Call wrote: > On 03-07 19:19, whistlez...@riseup.net wrote: [...] > > As I know many sites without js doesn't work. Anyway I don't understand > > how switching off js defend you from 0day browser bug. > > Maybe you mean that because many 0day concern javascript ? > > Yes, as well as the general category of speculative execution CPU > attacks, rowhammer-type attacks, evercookies that use javascript, > and/or whatever else I don't know about that is enabled by javascript. > It just seems to be required for many attacks that one reads about, over > time, and given that trend, probably some future ones, all from > downloading unknown code to run locally. For those fewer times when I do > enable it, I'm glad for OBSD's various protections, to further lower > risk. I think switching js off is one (very important) thing. But, there is more of it. Which is why I try to not load page-provided fonts and css at all. In css (or in certain browser-specific variation), one can embed js code, and same with svg file. I wonder if switching js off in browser would then result in not executing embedded js as well? Another fun read: Krebbs describes how browser extension has been sold by original author and then used by new owner to detect if user works on Wordpress or Joomla. If so, the "Page Ruler" injected small js snippet into edited webpage. https://krebsonsecurity.com/2020/03/the-case-for-limiting-your-browser-extensions/ I guess extensions work even with js switched off... Etc etc -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: Hardening browser
On Thu, Mar 05, 2020 at 12:25:56PM +0100, zeurk...@volny.cz wrote: > Me's been following this discussion w/ some interest. > > Personally, meuses lynx(1) (w/o the ports patches, as they interfere w/ > text field editing among other things), in image_links mode w/ feh(1). > Works like a charm :) I use lynx a lot, very nice tool. It also helped me to restart my browsing of gopher sites. There was plenty of them 20+ years ago, now it is just a handful of servers. But still, better than nothing. [...] > Occasionally, when really pressed, meruns 'tails', a specialized Lunix > distro, from a DVD on a spare craptop; at least that way, mecan get rid > of the bloated, buggy shit by simply turning off the machine. I do not know tails, only read about it. Using separate computers for different roles might be a way of the future. A very convoluted way. But one cannot count too much on security offered by modern popular cpus and there is always a chance to be struck by something unexpected: I have just read that bmp file from game server might make buffer overflow on client side. So, one machine for gaming, one for reading, one for shopping and one for work. And one for listing the music. I will never propose this kind of solution to normal people. :-) [...] > --zeurkous. > > -- > Friggin' Machines! Oh no, it is not the machines. It is their masters. -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: Hardening browser
On Thu, Mar 05, 2020 at 04:18:00AM +0100, Tomasz Rola wrote: [...] > As a side note, I sometimes get a bit obsessed upon seeing a program > which "sits idle" but scratches my disk every n seconds (and/or loads > my cpu with empty loops). A daemon can be hunted down and nailed. No > big deal. But a browser, it its grandiose form (say, ff) cannot be > nailed and used at the same time. I (partially) solved the problem by > putting ~/.cache-mozilla and ~/.mozilla on the ram disk. Now scratch > me if you can, browser. Actually, ~/.cache-mozilla and ~/.mozilla are I meant, ~/.cache/mozilla is a dead symlink. -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: Hardening browser
lways the same, same session, same settings, same everything as was saved to tar-files. The script is written with Elisp and duct tape, survived more years than I intended for it (planned to rewrite it in civilised Scheme dialect, but time too scarce to learn). Performance is better when the said dirs are saved in tar. No more zzz-zzz-zzz-ziping through multistaged directory structures. I measured the times, so I know. Compressing does not help in this case. Of course, that way I cannot use bookmarks in ff, but that is not a problem. I have already moved with bookmarking to org-mode. And good, because I doubt any browser would deal with ca. 100k bookmarks (once I was off the limits imposed by a browser, I kept adding and see where I ended). On the darker side of things, I am to introduce older family member to the World of Widely screW-W-Wed Web. The plan is to configure her browser like I do for myself (minus ramdisk, settings will be saved), but I am very much afraid the experience will be shocking and grievious for one of us. Either she will have to deal with noscript all the time, which is only so-so experience, but the alternative is that I keep imagining how she gets undead shit loaded from all over the WWW-world. I swallow noscript because I know what is the deal. Not sure if I can properly translate it to beginner user. I tried translating to medium-advanced younger user and failed miserably - she does not remember what I told her, not even the name "noscript" stays in memory, so after repeating ten+ times (over many months) I acknowledged my pitiful failure (fortunately, only I remember it) and reiteraited to the lair. Any ideas? The host is going to be laptop with Mint Xfce (yes, I have strong obsession against Unity), but I might move it to obsd one day (thanks to chronic lack of time I myself still had not moved out of Linux yet). TIA :-) -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: Softdep and noatime
On Sat, Nov 30, 2019 at 09:20:37PM +0100, Xianwen Chen (陈贤文) wrote: > Dear Mr. Rola, > > > I wonder what other will say about this, but I mount everything as > > noatime, since more than a decade, spinning or not. I assume this may > > Do you mount swap as noatime too, I'm curious? > > Yours sincerely, > Xianwen Hello, Frankly, I have never considered atime or noatime option for swap. I think there is not much use for atime in swap anyway. Access time for memory pages, this is another story. I guess some optimisation algorithms make use of this information. Ok, so not "everything", I only mount filesystems as noatime. :-) -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: Softdep and noatime
On Sat, Nov 30, 2019 at 06:12:42AM -0700, Raymond, David wrote: [...] > On SSDs in particular, is it worth setting noatime to reduce the > number of disk writes? [...] I wonder what other will say about this, but I mount everything as noatime, since more than a decade, spinning or not. I assume this may make lifetime a bit longer and decided it is better to be on safe(r) side. -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: Tools for writers
On Sat, Nov 02, 2019 at 03:00:28PM +, Oliver Leaver-Smith wrote: > Hello, > > What tools do people find useful for writing on OpenBSD? By writing > I mean long form such as novels and technical books, including plot > and character development, outlining, and formatting for publishing > (not all the same application necessarily) > > I have found a number which boast Linux support, but not really > anything that stands out which supports OpenBSD (aside from the > obvious LaTeX et al.) > > Mich appreciated > > ~ols I am not sure what is your ability to learn tools - no offence, but some people want to have it as WYSIWIG, period, and I am mostly ok about it (as long as they also do their cleaning). However, my unholy opinion is, if you plan for your words to be readable with the least problem say, twenty years from now, then you should stick with text based formats for, er, text and learn few tools that can process such format. So, - LaTeX for writing a book It is possible to have parts of a text in various files, which can be included into main file - various ways of developing plot, etc. It is possible to have many versions of same book, including chapters into them as separate files. And so on. I am not sure if a writer actually needs this much flexibility, but a lot is possible if you would like to mess with different ways to organize a book. - Emacs for editor This part is tricky, but I definitely prefer Emacs. Some prefer Vim and I agree it is very fine editor, but myself, I go with Emacs. I stay away from anything web based, browser based and Javascript based. All of those look like ticking bombs to me. When they go (not an unlikely event, IMHO) those depending on them are left to freeze. Or they will be dying a death of thousand worms loaded from some far away countries in their just-updated JS library. - Org mode for plot/characters and stuff Org mode is kind of program running inside Emacs (not really, but do I want to delve into talking about Lisp, loadable code and programmable editors). Or, it is a way to have one's own personal wiki in a file, without the need for web server and whatnot. Very handy, if you ask me. All those are tools and require some learning. In my case, I read a tutorial built into Emacs (say, an hour of reading + learning to press right keys), I read some chapters from Leslie Lamport book on LaTeX (say, maybe few hours of trying stuff inside Emacs and producing documents with it). As of Org-mode, I caught some basics and started going, then caught some more and there is still 98% or more to learn, but as I do not have to, I just use what I know and keep going. There are few more tools which might be useful for above case. - pandoc for converting from LaTeX to ODT (i.e. Open Office) - I have not used it but some people say it works - version control - whatever is easier, I have just set my own org-mode based "wiki" into RCS. RCS is amongst the oldest such system still in use, but I did not wanted to mess with other things, for a while. Now, if I make a mistake, press wrong key combo and delete half of my wiki, I might have better chance to recover from this error. There are many version control systems to choose from, I think most will work locally on your computer without prematurely exposing the book to the outside world. This email was written in Emacs, BTW. I get easy formatting for free. Of course, tools have quirks. I think so. I got used to them and forgot, so I am unable to say more about this. So maybe the learning experience will not be peachy rosy for you at first, but I would say positives prevail over time. HTH -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: BACK TO BASICS
On Fri, Oct 11, 2019 at 06:34:10PM +0200, Sylvain wrote: > Le 11 octobre 2019 18:08:22 GMT+02:00, "Theo de Raadt - dera...@openbsd.org" > a écrit : Holy fork, now this is a long email address... > >openbsd.s...@0sg.net wrote: [...] > > > >That's right, because monopolies always serve the public better! > > Rhetorically this answer sounds actually right... But I suspect it is given with a really long tongue in a cheek. Or maybe not? -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: Postscript printer recommendations
On Sun, Jul 14, 2019 at 12:09:20AM -0600, Jonathan Drews wrote: > On Sun, Jul 14, 2019 at 06:03:05AM +0200, Tomasz Rola wrote: > > On Sat, Jul 13, 2019 at 08:06:07AM +0200, Jonathan Drews wrote: > > > Hi Folks: I need some recommendations on what brand of printers will > > > work > > > with Ghostscript (Postscript). The cartridges for my 15 year old HP [...] > > > > I am not sure why you want to avoid CUPS. > > I have had difficulty getting cups to work in the past. I am just a simple > desktop user, so I really don't have a great grasp of computer > fundamentals. That begs the question as to why a desktop user would > use a complicated system like OpenBSD. Short answer: [...] Overally, I agree with your opinions except with that saying that OpenBSD is complicated. But it may be subjective. Try to imagine someone who wants to change wheels in a big truck, in a middle of a desert, with his bare hands (because the lousy car maker gave no tools). This is how my experiences with Windows were so far and *this* was complicated. > I never could get CUPS working in previous versions of OpenBSD. > Also, IIRC CUPS requires chown and chmod to certain /dev files. I am > loathe to do that. I really don't want to mess with root file > permissions. IMHO, if you need a service, then add your account to > the appropriate group in /etc/groups. > [...] > > > According to Xerox's web page on Postscript, they claim that > Postscript gives higher quality renderings: > > "Unlike PCL, PostScript is device independent. This means that the [...] > device. Specifically, the graphic objects will be consistent and in > some cases of higher quality than PCL." I smell marketing, unless they can show some examples which do not look like being specially crafted to prove their case. Of course, there might be differences - each time one wants to simulate a continuous line from square/round dots, there was plenty of research that went into achieving this illusion to satisfy the eye and I expect each of the great printer companies to have some patented algorithms of achieving the goal. But, since they are in the game for many decades, I expect the results to be comparable. Ok, so to sum up, so far you are ok with quality of your printer, just not so happy with Windows side? My own experience with CUPS was only so-so. About 7-10 years ago I connected my old (by then) HPDJ 840C and things did not work. So I mangled system a bit: I assumed one of the previous HPDJs was close relative to mine, copy-pasted description of either 630 or 620c (sumthing like this) and changed names to 840c (and maybe I changed some more, I really do not remember, it should be in old config files). From what I remember, CUPS caught up even though I was never sure why. Perhaps I had to resign from using the highest dot density supported by 840, but this was not a big deal since I wanted economic print, so I used 300 and 150dpi and dithering, rather than more dpis and full ink. So, CUPS worked for me, after a while. However, I am not sure if I would be able to help with setting it up - a year ago my twenty years old dj went into cartoon box (inks and printing heads - they were mostly ok but ink replacement dried up and I only printed once or twice a month, each time having to unmount the cartridge and wash heads in sumthin (sometimes isopropanol, sometimes lcd cleaner, which ever was at hand). The CUPS side, however, once it was up, it stood up, so I cannot complain. And it has got nice www interface, allowing me to set up few virtual printers (say, one for color print, one for 300dpi, and so on). But, it could probably be set up without CUPS. Perhaps you can arrange things so that you can try whichever printer works for you and is supported on OBSD, and compare same printed pages with whatever the bestest print thing there is in a nearby print shop? >From my experience (in my city and country) such shops are located near universities and cater to students, so they must be affordable. Chances are, the personnel will happily voice their opinions on the subject (just like any other opinion, incl mine, apply salt, especially that they may sell printers, too). -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: Postscript printer recommendations
On Sat, Jul 13, 2019 at 08:06:07AM +0200, Jonathan Drews wrote: > Hi Folks: I need some recommendations on what brand of printers will > work > with Ghostscript (Postscript). The cartridges for my 15 year old HP > Deskjet have gotten too expensive. I know Xerox makes some > Postscript printers. Are there any other manufactureres of Postscript > printers? I am running OpenBSD 6.5 as a desktop. Any advice would be > appreciated. Also, I just want to use printcap and lpd. I would like to > avoid CUPS. Kind Regards, > Jonathan I am not sure why you want to avoid CUPS. In case it is not clear, Postscript is just a programming language (stack based, somewhat like contorted Forth with graphics instructions, go have a /usr/bin/less on your favourite *.ps file and see). The printer "supporting Postscript" is just the one with CPU and enough memory to run interpreter inside the box. Thus, just like one feeds txt file to raw printer and gets raw txt display, so - I think - one feeds ps file and printer runs it, resulting in printing page (consecutive pages). I believe no special filter is necesary, because ps files start with magic line (well, some do not, possibly those produced by some proprietary programs, but I cannot recall right now) and chances are, PS-printer will recognize such line and act accordingly. However, I have seen documents, even single pages, with so many details that Ghostview running on relatively recent computer choked on it. I have no idea how much memory PS-printer can have, but I would not count on it having enough. My current desktop has 12gigs and four cores (not very fast), but obviously only one is tired by GV. I would try going with CUPS and printer with good resolution. Unless you have very specific needs requiring exactly such device (hard to tell, specific people have specific needs). But why running an interpreter and producing a bitmap onboard a printer would be better than running an interpreter (possibly up-to-dated) and sending a bitmap to the printer? Would one be able to spot a difference? Just curious. -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: Future of X.org?
On Mon, Jul 08, 2019 at 06:01:52PM -0400, Steve Litt wrote: [...] > I use Openbox with program instantiation via dmenu. Now here's the > thing: dmenu is written in pure X: No qt, no gtk, no xforms. Dmenu > does its job perfectly, so quickly that instantiation from hotkey is > imperceptable, as is menu changes in response to keystrokes. I did not know about dmenu, will have a look when spare time comes, thank you for a hint. [...] > If Wayland is now reliable and safe enough to use in OpenBSD, fine, > include it. But those who call for X11's removal are just asking for > trouble like the 2012-2015 systemd wars that plagued Linux and which > OpenBSD avoided. This new daemon was exactly the reason I subscribed to this list (and few others, to sniff on alternatives), even though various events kept me from installing OBSD (or anything else) so far. -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: Future of X.org?
On Mon, Jul 01, 2019 at 07:18:18PM +0200, Ingo Schwarze wrote: [...] > > Frankly, there is not much point in non-developers discussing > whether additions to base are acceptable. Feel free to suggest Well, whatever developers come up to, I hope I will be able to continue using FVWM, on top or inside the thing. I only post in this thread because I sense there are many people out there (I do not mean you) who equal graphical environment with the lookalikes of Windows and Mac (KDE, Gnome2 or 3). For me, that is too bloated and sometimes too inefficient. I had been using both KDE and Gnome for few years in total (and quite a few years ago, so my experiences are probably outdated), but after one upgrade KDE just stopped responding (possibly went into some O(n^2) loop while updating some internal database) and Unity just could not deliver for me (to say it politely). Also, cluttering display with permament menubars and this trash in the bottom had just lost its novelty after a while and became tiring to me. I make use of relatively huge virtual desktop (few-by-few screens) and open many windows. I would like to experiment with making some scripts for FVWM, to help me with juggling the mess around. As long as I can keep doing this, I will be happy (I guess). Thank you. Oh, and BTW I am huge fan of starting in text mode, so I turn off graphical logins whenever I can. -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: OT: hardware war with manufacturers (espionage claims)
On Sat, Jul 06, 2019 at 07:56:10PM +0200, Tomasz Rola wrote: [...] > machine, two of which killed more than six hundred people, before > someone turned the switch. As for now, there was a way to stop it. I have rechecked and the number of fatalities was 189 and 157, totaling 346 people. Please excuse my error. -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: OT: hardware war with manufacturers (espionage claims)
On Fri, Jul 05, 2019 at 09:49:02PM -0600, Theo de Raadt wrote: > Stuart Longland wrote: [...] > > > Basically your best bet: don't rely on a single vendor. It's harder for > > them to hide their espionage then as one vendor won't know how to hide > > another vendor's dirty deeds. > > Precisely. Most of the risks are in the bugs, and if you hit a problem > you'll be Dennis Muilenburg saying you didn't know (that phrase works > one way today, but if in the next few days he leaves his position, it > will work a different way). The unknown risk factors are first unknown > and potentially accidental, and secondly unknown and now we are supposed > to guess it wasn't accidental. Vendors are wired to increase > performance and noone judges security aspects, that the process where > the "accident" arises. Maybe we should suddenly accuse absolutely > everyone of malpractice! As if that will change anything... While the problems of spying on individuals are important and have an ugly side [1], I think nowadays [2][3] that long term, the real problem will be autonomous hardware. Just like two recent catastrophes involving Boeing. On the one side, it may be seen as unfortunate sequence of human errors, fueled by greed (fueled by procreation drive). On the other side, the very same decisions led to making a machine, two of which killed more than six hundred people, before someone turned the switch. As for now, there was a way to stop it. I wait in terror for "our devices never stop". [1] I am not sure, do they have a nice side? perhaps if certain kind of crimes could be fought with it? [2] This can change in the future - GIGO, FIFO, you all know it [3] Oh, I did not come to it all by myself. If some of you have a chance, try reading Stanislaw Lem. Some of his works have even been translated to English (but I cannot say how well, opinions say very well, but then again US editors like changing what they print from original versions (anecdotic evidence, surprisingly too many to ignore)). Do not be misled by his joking tone. The man survived in the heart of WW2 and witnessed both post-war and Cold War. People mostly take things at the face value. He told them jokes about humanity and readers had a good time. Some, not so good.[4] [4] For shortified super-short version, try Henry Kuttner's "Twonky". > So this is misc, which is full of lots of talk about nothing, by people > who can't change the ecosystem. Having worried vocally about this > before, I know I can't change it. Pretty sad to see people who are even > less capable find the energy to moan about it. Especially americans. > Know what I mean? Humans, when faced with inevitable, do: 1. forget it is inevitable 2. phantasise about something nice, to kill time while waiting for it Do not expect too much from a jello between the ears. For our limitations, we came surprisingly far and long, albeit some are saying there will be cost and paying the bills and dies irae et calamitatis. Who knows. Nothing in nature is free, eh? I guess there is a lot of shifting stuff around, so those who pay the bills are not those who got the credit. Sorry for being so much offtopic. On the other hand, we are living in a future, so maybe this is more on topic than one would expect. People here are involved in creating significant portion of our lifes. Not that I see any way to make use of it, I am too apathetic for this. -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: Cheaper alternatives for APC UPS
On Mon, Dec 17, 2018 at 09:47:25PM +0100, Radek wrote:
> Hello,
>
> could you recommend me any UPS brands *cheaper* than APC that are
> fully supported in OpenBSD?
> I always use APC, managing them via USB and apcupsd(both servers and
> clients) and PowerChute(windows clients). It works like a charm.
> APC is quite expensive brand so I am looking for any cheaper
> alternatives.
I am not sure about "supported", but for a while I used Fideltronik
and was satisfied (battery failed after some years of good job). Alas,
it gave approximated sinus, and I want true one nowadays. The only
choice available in the limits of my budget is either used APC or
another brand, new European-by-the-name-seemingly. I used a second
hand APC (1000-something, blinking leds model), after some years
batteries died and I decided to try this other option. It worked fine
for two years, then died. Upon inspection I found that certain part
inside looked like burned, with ash on it (possibly burned
plastic). Also, I cannot bet on it because I stuffed the battery
somewhere ("hey I can reuse that for a hobby!") and am not sure where
it is, but I would say there was single 6v unit inside. As far as I
can tell, the ups never reported more than 50% load, so I do not think I
overworked it.
Anyway, I could easily lift its battery on two fingers, maybe
three. In both APCs (I am on another second hand now, again
1000-something but now with lcd display) there are two 12v batts (I
think) and I would rather not want to lift any of them other than on
full arm. The first second-hand will probably be inspected and turned
into spare unit, because the current one will finish itself too, one
day. But the batts can be replaced in both models.
HTH
--
Regards,
Tomasz Rola
--
** A C programmer asked whether computer had Buddha's nature. **
** As the answer, master did "rm -rif" on the programmer's home**
** directory. And then the C programmer became enlightened... **
** **
** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: Common Lisp and OpenBSD
On Sun, Nov 25, 2018 at 05:17:20AM -0500, Programmer wrote: > There don't seem to be any Common Lisp libraries available as > packages. I'd be interested in packaging the most common and mature > Common Lisp libraries, but I'm not certain who I'd discuss this with. > > I'd appreciate any help with getting started contributing to OpenBSD. Dear Programmer, I am not going to tell you what to do, but if I had enough free time to consider such projects, I would go and ask if Quicklisp project needs some help from me (in case you do not know, it is a package installer for Common Lisp). https://www.quicklisp.org/beta/ http://blog.quicklisp.org/2018/10/october-2018-quicklisp-dist-update-now.html Zach Beane is the author (it seems) and is doing enormous job. It looks like in best case you would be replicating his work, which, with all due respect to OpenBSD, might get ignored if you cannot keep up with updating ports at his speed. I, for one example, would rather stick with quicklisp, because it is going to work everywhere when CL is installed (well, mostly). While I have never done it, I guess making one system wide quicklisp install is easy to do, probably just add user and have his quicklisp files word- or group readable. And have users read this guy's setup.lisp from quicklisp install. And quicklisp allows me to keep using old versions of installed libs, which ports cannot give me, AFAICT. This one feature is worth going QL way. At least to me. HTH -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: find the process that heavily uses a disc
On Tue, Oct 16, 2018 at 02:22:16PM +0200, Rudolf Sykora wrote: > Hello, > > please, how can I monitor disk usage and tell > what process is using it heavily? > > (I hear [and see] that the disk is being used, > but cannot think of a process that would cause > it.) I would start with atop, it has a column for RDISK and WDISK. If you cannot atop, there is about 78% chance that killing a browser will solve the problem. HTH -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: ksh equivalent to shell-expand-line
On Sun, Oct 07, 2018 at 11:17:37PM +0200, John Ankarström wrote: [...] > > To which message is this a response? It seems I haven't received > it, but I'd like to read it. Tomasz? I have sent you a message offlist, see if you have it. -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: ksh equivalent to shell-expand-line
On Sun, Oct 07, 2018 at 07:47:46PM +0200, Klemens Nanni wrote: > On Sun, Oct 07, 2018 at 07:30:15PM +0200, Tomasz Rola wrote: > > Another trick may be executing the line with echo prepended - should > > do all expansions and write what will be executed. I think it is not > > going to work too well if for loop is being echoed, and other such > > things, so perhaps quoting a command and echoing would do the job. > This will break any non-trivial construct including pipes, command lists, > loops, (nested) quoting, et al. And let's not forget about redirections - any writing/appending inside expansion will make echoing it even more non-trivial. However, the same can be said about M-C-e in command prompt - how is the shell going to know it should not expand this particular part, because it calls a script which appends to / deletes from database? And lets say it deletes not quite what we want? Because we are prototyping on live command. Which makes me say again, if this is such nontrivial, then I choose writing a script. -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: ksh equivalent to shell-expand-line
On Sun, Oct 07, 2018 at 10:13:16AM +0200, Otto Moerbeek wrote:
> On Sun, Oct 07, 2018 at 08:48:52AM +0200, Tomasz Rola wrote:
>
> > On Sun, Oct 07, 2018 at 12:03:31AM +0200, Klemens Nanni wrote:
> > > On Sat, Oct 06, 2018 at 09:38:42PM +0200, John Ankarström wrote:
> > [...]
> > > And yet, it disregards quoting and will errornously expand the following
> > > example into multiple words instead of one:
> > >
> > > bash-4.4$ echo "$(echo a b)"
> > > bash-4.4$ echo a b
> >
> > Just in case it matters to anybody:
> >
> > $ echo "$(echo a b)"
> > a b
> > $ bash --version
> > GNU bash, version 4.2.25(1)-release (x86_64-pc-linux-gnu)
> >
> > Looks like something changed in between?
>
> This is not about executing the line, it's abouty expanding using Ctrl-Alt-e
I can see now (side note to myself: do not ever never again reply to
emails before going to sleep at morning, sorry).
So, can this problem be described as that OP cannot expand this stuff
in his memory (this jello ram between the ears), because it has got
too complicated? Perhaps this can be helped by writing things into a
proper script? I performed a lot of $() things in cli but never
learned about M-C-e, so I assume I never did things that required this
trick. Hence a script suggestion.
Another trick may be executing the line with echo prepended - should
do all expansions and write what will be executed. I think it is not
going to work too well if for loop is being echoed, and other such
things, so perhaps quoting a command and echoing would do the job.
Seems like it works in bash as I hoped:
==>$ echo "for i in $(seq 3); do circle ${i}; done"
for i in 1
2
3; do circle ; done
HTH
--
Regards,
Tomasz Rola
--
** A C programmer asked whether computer had Buddha's nature. **
** As the answer, master did "rm -rif" on the programmer's home**
** directory. And then the C programmer became enlightened... **
** **
** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: ksh equivalent to shell-expand-line
On Sun, Oct 07, 2018 at 12:03:31AM +0200, Klemens Nanni wrote: > On Sat, Oct 06, 2018 at 09:38:42PM +0200, John Ankarström wrote: [...] > And yet, it disregards quoting and will errornously expand the following > example into multiple words instead of one: > > bash-4.4$ echo "$(echo a b)" > bash-4.4$ echo a b Just in case it matters to anybody: $ echo "$(echo a b)" a b $ bash --version GNU bash, version 4.2.25(1)-release (x86_64-pc-linux-gnu) Looks like something changed in between? -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: Some highlights: Emacs 21.4 and 25.3
On Tue, Oct 02, 2018 at 04:40:53PM -0400, John M wrote: > Personally I use Emacs 25.x on OpenBSD 6.3, with the caveat being that > I rely on a number of customizations to normalize behavior to be what I > expect. I would suggest using whichever version annoys you the least. Yeah. After learning that 25 has Webkit support and 26 has threads, I have made resolution to manually compile Emacs for myself. Since I am yet to install OpenBSD, I have no idea what are defaults there and whether I would like them, but it looks like I have to check for such things nowadays. Which makes inclusion of 21 even more understandable and plausible safe choice. > >> And I am tired that in some modes I cannot get emacs to stop > >> writing things (like indentation) that I do not type. > > > > I believe there is a variable to customize for this behaviour. I will > > know the variable name when I find it in Elisp code down there in > > sources. After that, googling for this name will be very easy. [...] > > This may be a bit off-topic but the feature responsible for this is > 'electric-indent-mode', which is enabled by default in 24.4 or later. > > http://www.gnu.org/software/emacs/manual/html_node/emacs/Indent-Convenience.html#index-Electric-Indent-mode > > Put (electric-indent-mode -1) somewhere in your Emacs configuration > when using 24.4 or later. Ah so this is the name. Thank you! -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: Some highlights: Emacs 21.4 and 25.3
On Tue, Oct 02, 2018 at 03:55:31PM +, Roderick wrote: > > On Tue, 2 Oct 2018, Solene Rapenne wrote: > > >emacs 25 has a X11 flavour -athena which do not use gtk, but you need > >to build it from ports, there is no package for it. > > And indeed I do that. > > I thought that perhaps 21.4 is more stable, or less bloated ... > > Interessting remains to know, what the reson was. Your remarks prompted me to have a look myself - so those are just my wild guesses, but: - a comparison between announcements for 21.1 and 22.1 http://lists.gnu.org/archive/html/info-gnu-emacs/2001-10/msg9.html http://lists.gnu.org/archive/html/info-gnu-emacs/2007-06/msg0.html tells me that support for GTK started with 22.1 - and if so then 21.4 is the latest bugfixed version without it, while still enabling color themes (and custom fonts?), which are very nice to have (me being color abuser). - myself, I am using 23 and 24, and comparison of their "concept index" info nodes shows there are 1582 and 1863 items, respectively. Some of those new concepts were introduced earlier and only documented in 24 but this gives a glimpse into amount of ongoing changes. There are some new Elisp functions in 24 and various sets of installed Elisp files for each, which makes supporting them both in my dot-emacs an interesting puzzle (not always succesfull). > And I am tired that in some modes I cannot get emacs to stop > writing things (like indentation) that I do not type. I believe there is a variable to customize for this behaviour. I will know the variable name when I find it in Elisp code down there in sources. After that, googling for this name will be very easy. Before this happens, I will continue to use 23 and 24 (23 does not show me indent problem), but I feel prompted to have a look at 21 as well (but then even more puzzles for dot-emacs). My guess is, all those inconveniences are introduced to make more users into looking under the hood. I have not really cared much about such detail until I played with elpa too much and had to manually unkcuf it. -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: Remiss on my personal and server security practices, offering server usage to outsiders
On Wed, Sep 19, 2018 at 11:09:20AM -0700, Chris Bennett wrote: [...] > I still would like to know about httpd's owner:group and permissions on files > not served to the public. I am not sure if somebody answered you offline, but my reasoning goes like this: 1. httpd runs and has said files writeable to itself (due to same owner:group) (if Perl is a no-no, how about PHP, a popular choice with problems of its own [judging from bug reports from time to time]) 2. someone finds a security hole 3. your scripts in Perl/PHP/C++ or whatever become overwritten by httpd 4. from now on the scripts will be not only doing what they were doing upto now, but also whatever additional code someone appended to them 5. ... something nasty HTH -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: wifi gui manager
On Wed, Aug 22, 2018 at 08:49:57AM +0300, Consus wrote: > On 18:07 Tue 21 Aug, Stuart Henderson wrote: [...] > > They're even slower and uglier if you have to run the m4 stuff to > > *generate* them before you can even run them, and may not work as > > intended if they're run through a version of autoconf which they > > weren't designed for. > > That's why we should nuke autloluz in favor of something else. Just > plain Makefiles for example. Or meson, I heard it's okay. I always thought that autoconf had been written exactly because "plain Makefile" was unable to make it. It is not really that slow, unless one insists on recreating config and Make* files every time they want to compile a project - like, they would expect their system changed and installed some new stuff during five minutes between compiles. BTW, I sometimes compile from sources (not ports, just source*tgz from the respective websites) and I usually find that config script provided is ok, so I had to regenerate one such file maybe two years ago (via autoconf). HTH -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: Lumina-Terminal on OpenBSD
On Sun, Jul 08, 2018 at 01:45:09PM -0400, rehcla wrote: > I am pretty sure there is absolutely nothing wrong with me! > > But thanks for the explanations, which provided a working solution > for me... Last but not least it inspired me to set a second desktop > with FVWM to learn more about terminals... FVWM makes great minimal environment, IMHO. If you need multitabbed terminal, I have had (so far) good experience with roxterm, and I also use uxterm a lot - it is a Unicode-enabling wrapper around xterm. -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: How to copy n bytes from stdin to stdout?
On Sun, Jun 24, 2018 at 10:53:37PM -0400, Steve Litt wrote:
> On Thu, 21 Jun 2018 00:56:04 +0200
> Tomasz Rola wrote:
>
[...]
> > Craps. I have consulted OpenBSD's manpage for dd and there is no
> > mention of iflag. So this will not work on OpenBSD. I will have to
> > rethink this, sorry.
> >
>
> Untested...
>
> int main(int argc, char* argv[]){
> long l = atod(argv[1]);
> while(l--){
> if (c = getc(STDIN) != EOF)
> putc(c, STDOUT);
> else
> break;
> }
> return 0;
> }
>
> I haven't tested it so it might not be exactly right, and of course
> error handling would need to be added, but you know what I mean. IIRC
> getc() and putc() are very well buffered so it will be fast. In my
> youth I wrote similar functions using low level read() and write() and
> doing my own buffering, and those things were *really* fast, but I
> think that's overkill in this century.
>
> As far as finding command line tools that do it, if that's becoming
> hard to do, why not just write a 10 line program?
Actually, I have written few such programs to satiate my own curiosity
- I was dragged away from computer and in the meantime, others joined
thread and even wrote nice buffered version of solution in C. I pitted
this solution against my programs (in C, with fgetc/fputc and Common
Lisp, with read-sequence/write-sequence) and head-c.c was many times
faster (about hundred or more times) than my programs.
I am not sure if there is performance difference between fgetc/fputc
and getc/putc. Man says getc are macros around fgetc. Might be worth
checking, but I guess no difference.
My curiosity also "wanted" to know how much of performance hit was to
be expected when writing best to my knowledge optimised Common Lisp vs
simplistic C - they were similar in performance, with CL compiled by
SBCL and few times slower, and head-c.c had beaten them both by many
lengths. I am a bit surprised that in CL, performance was about the
same, whether reading one byte or many at once. Perhaps I will find a
way to speed it up some more.
As of finding command line tools, I had working script in about an
hour (and buggy one in few minutes). Buggy, because "dd | dd" is bad
idea, and after finding better options for using dd in my script -
which worked, but under Linux - I had also found out they would not
work in OpenBSD.
So, I consider it a worthy lesson for myself. Next time, I might just
fire up Emacs and write a script in CL (mostly, because this is what
is comfy for me nowadays, and I will not object against having compiled
script for free). Or something similar, or maybe even do it in C, why
not.
BTW, the version of nread.sh (improved options) was on par with
head-c.c, so writing a script with right things inside is very good
choice, too. If the script actually works :-) .
While the speed is not big problem for input of about 1 megabyte, it
becomes a problem when gigabytes are copied.
--
Regards,
Tomasz Rola
--
** A C programmer asked whether computer had Buddha's nature. **
** As the answer, master did "rm -rif" on the programmer's home**
** directory. And then the C programmer became enlightened... **
** **
** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: How to copy n bytes from stdin to stdout?
On Thu, Jun 21, 2018 at 12:44:14AM +0200, Tomasz Rola wrote: [...] > => (591 60): cat nread > #!/bin/sh > > # nread n - read up to n bytes from stdio, put them on to stdout > > N=$1 > > dd bs=512 count=$((N / 512)) iflag=fullblock 2>/dev/null > dd bs=1 count=$((N % 512)) iflag=fullblock 2>/dev/null Craps. I have consulted OpenBSD's manpage for dd and there is no mention of iflag. So this will not work on OpenBSD. I will have to rethink this, sorry. -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: How to copy n bytes from stdin to stdout?
On Thu, Jun 21, 2018 at 12:02:14AM +0200, Maximilian Pichler wrote: > Your script is incorrect. > > $ dd if=/dev/zero bs=1 | ./nread 1234567 | wc -c > 0+2411 records in > 0+2411 records out > 2411 bytes transferred in 0.038 secs (62579 bytes/sec) > 135+0 records in > 135+0 records out > 135 bytes transferred in 0.001 secs (126148 bytes/sec) > 2546 > I have slightly modified the script to ease debugging. Also, slight mod to read full blocks - I was not aware that strange things can happen when two dd's feed one another in a pipe. => (591 60): cat nread #!/bin/sh # nread n - read up to n bytes from stdio, put them on to stdout N=$1 dd bs=512 count=$((N / 512)) iflag=fullblock 2>/dev/null dd bs=1 count=$((N % 512)) iflag=fullblock 2>/dev/null => (591 61): md5sum (591 65): dd if=/dev/zero bs=1 2>/dev/null | /usr/bin/time nread 1234567 | wc -c 0.14user 3.00system 0:03.55elapsed 88%CPU (0avgtext+0avgdata 768maxresident)k 0inputs+0outputs (0major+737minor)pagefaults 0swaps 1234567 => (591 66): cat HUGE | /usr/bin/time nread 1234567 | wc -c 0.00user 0.01system 0:00.02elapsed 54%CPU (0avgtext+0avgdata 768maxresident)k 0inputs+0outputs (0major+734minor)pagefaults 0swaps 1234567 -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: How to copy n bytes from stdin to stdout?
On Wed, Jun 20, 2018 at 08:20:16PM +0200, Maximilian Pichler wrote: > On Wed, Jun 20, 2018 at 7:17 PM, Tomasz Rola wrote: > > But seriously: man sh. > > Are you saying there is a shell built-in that does this? If so, which one? => (591 13):cat nread #!/bin/sh # nread n - read up to n bytes from stdio, put them on to stdout N=$1 dd bs=512 count=$((N / 512)) dd bs=1 count=$((N % 512)) => (591 14): md5sum (591 15): chmod a+x nread => (591 16): cat HUGE | /usr/bin/time ./nread 1234567 | wc -c 2411+0 records in 2411+0 records out 1234432 bytes (1.2 MB) copied, 0.0122527 s, 101 MB/s 135+0 records in 135+0 records out 135 bytes (135 B) copied, 0.000620305 s, 218 kB/s 0.00user 0.01system 0:00.02elapsed 57%CPU (0avgtext+0avgdata 768maxresident)k 0inputs+0outputs (0major+731minor)pagefaults 0swaps 1234567 Total time is well below 1s. If you want faster, then you have to write it in C or assembly. -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: How to copy n bytes from stdin to stdout?
On Wed, Jun 20, 2018 at 06:50:06PM +0200, Tomasz Rola wrote: [...] > > Maybe suggest to the teacher that she sticks to numbers divisible by > 512? That is what haxorz do. But seriously: man sh. -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: How to copy n bytes from stdin to stdout?
On Wed, Jun 20, 2018 at 06:35:49PM +0200, Maximilian Pichler wrote: > On Wed, Jun 20, 2018 at 6:27 PM, Tomasz Rola wrote: > > On my Linux box: > > ? > > > cat HUGE | /usr/bin/time dd bs=1 count=1234944 | wc -c > > stdin might be something much faster than your disk, in which case the > relative cost of bs=1 increases. So is this the problem with slow disk? > > cat HUGE | /usr/bin/time dd bs=1024 count=1206 | wc -c > > Doesn't work for prime numbers. ;) Maybe suggest to the teacher that she sticks to numbers divisible by 512? That is what haxorz do. -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: How to copy n bytes from stdin to stdout?
On Wed, Jun 20, 2018 at 06:01:21PM +0200, Maximilian Pichler wrote: > On Wed, Jun 20, 2018 at 5:50 PM, Solene Rapenne wrote: > > it's slow because it flushes the output every byte, what would you > > expect? Maybe you should do in a different manner. > > I know, my question is what such a different manner might look like. :) On my Linux box: cat HUGE | /usr/bin/time dd bs=1 count=1234944 | wc -c 1234944+0 records in 1234944+0 records out 1234944 bytes (1.2 MB) copied, 4.33782 s, 285 kB/s 0.33user 4.00system 0:04.34elapsed 99%CPU (0avgtext+0avgdata 772maxresident)k 0inputs+0outputs (0major+249minor)pagefaults 0swaps 1234944 cat HUGE | /usr/bin/time dd bs=1024 count=1206 | wc -c 1206+0 records in 1206+0 records out 1234944 bytes (1.2 MB) copied, 0.00895034 s, 138 MB/s 0.00user 0.00system 0:00.01elapsed 66%CPU (0avgtext+0avgdata 768maxresident)k 0inputs+0outputs (0major+248minor)pagefaults 0swaps 1234944 -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
