Posts by JdeBP@tty0.social
(DIR) Post #AUjGKwoglkzgdwQKW0 by JdeBP@tty0.social
2023-04-17T02:29:09Z
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@mjg59 You forgot a tiny bit of added horror. It's actually _unreal_ mode until the first segment register load. In _real_ mode, the segment base addresses don't work that way.https://superuser.com/a/345333Then, of course, for older operating system support we have the firmwares that report their reserved areas as free memory. (-:https://unix.stackexchange.com/a/461774/5132#IntelArchitecture
(DIR) Post #AUjlLe3z4mwTLjOGw4 by JdeBP@tty0.social
2023-04-17T08:16:59Z
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@mjg59 It's in the processor manuals, complete with the initial base addresses used, which aren't possible to obtain in real mode, and a note on the special mode of operation until the first segment register reload.This isn't an undocumented thing. There are two paragraphs on this in §9.1.4 of my 2010 copy of the Intel System Programming Guide.And it's the whole of §14.1.5 of my 2007 copy of the AMD System Programming manual.#IntelArchitecture
(DIR) Post #AV1BBe6TyL5D4elpC4 by JdeBP@tty0.social
2023-04-25T17:57:47Z
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@charadon Is it your first encounter with a daemontools-family system?#runit #s6 #daemontools
(DIR) Post #AV1CuYNKDUnUIFcrdw by JdeBP@tty0.social
2023-04-25T18:17:08Z
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@charadon @RL_Dane The whole "init scripts are massive shell scripts" was always a bit misleading, although I _have_ seen several lengthy Mewburn rc scripts, especially in the networking parts of the system.Mewburn rc was designed with a bunch of shell function helpers to cut down on common script code. Even van Smoorenburg rc, in a push to modernize in the early 2010s that was spurred on by the advent of systemd, gained a mechanism for much shorter scripts.#rc #Mewburn #vanSmoorenburg
(DIR) Post #AV7XF27EW3FYM4twoq by JdeBP@tty0.social
2023-04-28T19:33:18Z
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@penguin42 @cks That's the thing. The GNU egrep and fgrep _already are_ shell scripts. Paul Eggert added this change _to those shell scripts_.https://debbugs.gnu.org/cgi/bugreport.cgi?msg=17;att=1;bug=49996;filename=0001-egrep-fgrep-now-obsolete.patch#GNU #grep #egrep #fgrep
(DIR) Post #AVLdnPlWPdU3UHxk8W by JdeBP@tty0.social
2023-04-29T18:56:47Z
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@Toasterson You want SMF to have more features? Which ones, if so?Or you want some more of the features that are in SMF to be added to some other system? Which ones, and why?#Illumos #nosh #SMF
(DIR) Post #AVLdnSOwc2Crf8QFrU by JdeBP@tty0.social
2023-05-05T13:00:30Z
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@ToastersonConverting systemd unit files to things suitable for SMF?Speaking as the only person in the world who has written a #systemd unit converter, to my knowledge: this is not a trivial task.See https://jdebp.uk/Softwares/nosh/guide/commands/convert-systemd-units.xml@ska has just written up a page on unit file conversions, and xe points out, as I do, that there are architectural mismatches in some areas.See https://skarnet.org/software/s6/unit-conversion.html#s6 #nosh
(DIR) Post #AWe6y7aV0DMgHTrTjU by JdeBP@tty0.social
2023-06-13T10:36:29Z
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@NGIZero @sovtechfund I should put in a claim for writing some infrastructure documentation. (-:https://jdebp.uk/Proposals/Debian-hostname.xml
(DIR) Post #AWf8wKXQHCLsvuekbo by JdeBP@tty0.social
2023-06-06T16:15:41Z
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@leah @cks That's my login shell too, generally. And I just found a quirk in it if one upgrades from 5.2 to 5.3. I was going to post a Q&A to StackExchange. But there's a strike, now.Have you tried the Watanabe shell? That has a help command, too.#zsh #yash
(DIR) Post #AWf8wLVgf8YdwoqsXg by JdeBP@tty0.social
2023-06-06T16:53:29Z
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@leah @cks In other popular non-SUS commands news there are jot, ifconfig, dnsqr, stat, fetch, less, and clear.Do you think that the fgrep purists ought to not clear their screens, too? (-:Or use any other name for their compiler than c99? (-:Or be required to use only od to view non-text files? (-:#POSIX #Unix
(DIR) Post #AwUURPYuargtDp4ZDU by JdeBP@tty0.social
2025-07-25T11:29:06Z
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@dalias @ska @lanodan @navi One of those someones was Rob Pike in 2004.https://interviews.slashdot.org/story/04/10/18/1153211/rob-pike-respondsAnd the underlying kernel change happened in 2007.https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b6a2fea39318e43fee84fa7b0b90d68bed92d2baInterestingly, modern #FreeBSD has a sysctl() limit (kern.ps_arg_cache_limit) on how large processes can resize their argument block and environment string block and still have it show up in the ps command.I just raised mine to 768 bytes, coincidentally. I could have got away with just 512, I think.#Linux
(DIR) Post #AzhnW2j2jI08CnDEEy by JdeBP@tty0.social
2025-10-29T07:30:53Z
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@ljrk @lanodan @ska In this case, it apparently goes back to the original AT&T Unix concept of sessions, when BSD process groups were added to them.I pulled my copy of Pate down from the shelf and this restriction was in either XENIX or System 5 (Pate is not completely clear) and hence why it was standardized.Quite why #OpenBSD later gained this restriction is a mystery from the commit log. It wasn't in #NetBSD but added by @millert in 2000.https://github.com/openbsd/src/commit/b3fe5974ccb2d4b668d93844f3e74d0a4e3306b8#FreeBSD #Illumos
(DIR) Post #AziM9jFJyAmloePCEq by JdeBP@tty0.social
2025-10-29T21:55:06Z
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@ljrk @lanodan @ska Sadly, it is a common failing of manual pages to parrot the SUS and its wording for implementation-defined behaviour rather than document the concrete operating system at hand:Whilst the #Illumos manual page leaves the loophole open, the actual kernel code does not make same-session checks and never returns EPERM from getpgid().https://github.com/illumos/illumos-gate/blob/044718b30e6a998dddd440a2d90357cc7eb053ad/usr/src/uts/common/syscall/pgrpsys.c#L152#Tribblix #OpenIndiana #OmniOS #getpgid
(DIR) Post #B0SUKVTe1VJXrkeC4O by JdeBP@tty0.social
2025-11-21T03:27:41Z
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@rl_dane It looks like §3.5 of the #FreeBSD Handbook is well out of date.Every user's home directory getting to be its own #ZFS filesystem goes back as far as when ZFS as root was first adopted in PC-BSD.And there are a few other PC-BSD conventions with ZFS, such as /usr being a non-mounted ZFS filesystem.
(DIR) Post #B0SUKWoF4PNtzvI9oW by JdeBP@tty0.social
2025-11-21T03:32:02Z
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@rl_dane You're a bit optimistic about #Linux doco, there, by the way. Weeks! (-:Many how-tos and such from the #LinuxDocumentationProject notoriously date from the 1990s and were last updated two decades ago.One wouldn't know from TLDP about the Bourne Again to Almquist shell switchover, for instance. And there's PalmOS and Psion as hardware platforms, but no #RaspberryPi.
(DIR) Post #B0SUKcdpO2cS5MSvPk by JdeBP@tty0.social
2025-11-21T04:01:08Z
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@rl_dane > How do you scroll up in the console???Speaking of which:#Linux dropped the #scrollback mechanism from its kernel #VirtualTerminals entirely, in version 5.9, released in September 2020.The "Linux keyboard and console HOWTO" in the meanwhile is dated 1998.There are quite a number of outdated StackExchange answers that haven't been corrected for the new reality, too. So it's not solely the #LinuxDocumentationProject that was written "weeks ago". (-:https://superuser.com/a/281876/38062
(DIR) Post #B2VWOngN6uIzoqBXpw by JdeBP@tty0.social
2026-01-21T09:47:11Z
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@ska My schools did not teach C or any language like it.I learned about -- and #getopt from a combination of FidoNet, Usenet, and a 1985 book on Unix by Eric Foxley.The habit of using -- probably cemented when I wrote a load of command-line utilities for DOS and OS/2 in the 1990s which all supported an end-of-options marker in their command-tail parsing library.https://groups.google.com/g/comp.os.os2.utilities/c/415LDKL3_Lw/m/P9tPDLd7VAUJI made use of what my own tools could do. (-:@cazabon #os2clu #dosclu