4 ms·

One of my pet-peeves with C projects is that it's so often more or less "works on my machine" when written by Linux users (as a Windows and FreeBSD user it ofte

One of my pet-peeves with C projects is that it's so often more or less "works on my machine" when written by Linux users (as a Windows and FreeBSD user it often hits you on both those platforms). The article highlights a typical piece: #if !(defined __GNUC__ || defined __clang__ || defined __TINYC__) # define __attribute__(xyz) /* Ignore */ #endif There is no reason that !defined check to not include a check for __attribute__ already being defined (a custom compiler author could then force an define for __attribute__ that translates to an internal __mycompiler__attribute__ replacement by default). But outside of that, just trying to compile on FreeBSD you often run into systemd dependencies or other non-posix behaviors (Not to mention on Windows but I'm not here to bring on flamewars so I'll leave that part).

formerly_proven 5mo ago
For a bunch of software categories there isn't really much point to support Windows at all these days. We've had "developed for unix, ported to Windows" software for a long time and it often doesn't work that well, because the agreement even for fairly basic stuff is not that large between the two.
- zephen 5mo ago
  There's portability between systems, which as you note, has ever-diminishing returns. Then there's portability between compilers, which, as the article notes, glibc is also completely hostile to (except for anointed compilers) for no good reason whatsoever.
  - account42 5mo ago
    > which, as the article notes, glibc is also completely hostile to This is neither true nor claimed by the article.
    - zephen 5mo ago
      The article specifically states "If you aren't gcc, clang, or tcc, tough luck." It doesn't work. For no good reason. Because there are a few anointed compilers. That it wasn't on purpose doesn't make it not hostile.
- deleted 5mo ago
  [deleted]
- jdw64 5mo ago
  in Asia, and over here, Windows is the de facto standard while Linux is actually a poor option. Almost all of the infrastructure is written for Windows, so the second you switch to Linux, you're fighting an uphill battle just to do basic tasks. Seeing this makes you realize that our worldview is entirely shaped by the ecosystem we live in
- whizzter 5mo ago
  1: My point isn't "developer on unix, ported to Windows", it's "developed on linux, maybe works elsewhere". 2: You could easily compile Samba yourself for FreeBSD in the past, last time I tried a new version it broke in what I remember being due to linux-isms (yes there is ports, but being reliant on older versions if ports maintainers can't keep up isn't a good thing). 3: The only "fairly basic" stuff that's hugely different is mostly the absence/reliance on shell-scripts (when building), but that has little to do with the actual code function (Personally I often used Node scripts in those scenarios, Python scripts would probably be an improvement since there's no reason it couldn't be everywhere). I used to use Tremor to decode Ogg audio (no UI needs, just binary data in, arrays of primitive values in audio buffers out), early versions were easy to compile under Windows but building later versions were buried in shell scripts generating headers,etc for no real good reason (maybe to help port when working on a Linux workstation to other embedded devices but made the code less easily compilable by default), the core functionality only really needed a C compiler as early versions showed. I can agree that something with advanced UI's like Blender (that relies on GL/3d rendering for UI) might not be easily portable, but when algortihm libraries often requires heavy reworking it's not a good thing (Here I think Github has helped since people has had an easier time to contribute, it's a sad thing that people are moving away due to the AI-crap). In the end, it's not about _actual_ differences but more of a superiority complex of Linux users that is the main roadblock.
  - rootnod3 5mo ago
    Exactly, the amount of patches needed in many FreeBSD or other BSD ports just to appease the Linux-centricity is bonkers. And many times the changes aren't even that grave.
  - matheusmoreira 5mo ago
    Superiority complex? How many times have we been told that we're entitled freeloaders for expecting Linux compatibility work from others? Insulted by people who use dominant platforms that get all the commercial support while we get literally nothing? Reduced to reverse engineering stuff with no documentation and zero help? Pretty wild to watch this unfold. Now that Linux is finally coming out ahead, as it should, because people are finally writing software for it... Suddenly we're the bullies.
BadBadJellyBean 5mo ago
If it is an open source project then that is quite alright with me. An open source author doesn't need to support all platforms. Only those they care about. If someone else wants support for another platform they have the source.
- whizzter 5mo ago
  Yeah, I think I did miss mentioning that my comment was more weighted on simpler cli tools or library projects (file format readers,etc). I don't expect anyone writing GUI tools or more high-perf servers to spend their time porting to other platforms (trying to compile GTK on Windows wasn't for the faint of heart).
kps 5mo ago
>One of my pet-peeves with C projects is that it's so often more or less "works on my machine" “All the world's a VAX” https://groups.google.com/g/comp.lang.c/c/CYgWkWdWCcQ/m/thMt3RfByAgJ?pli=1 https://groups.google.com/g/comp.lang.c/c/CYgWkWdWCcQ/m/thMt... https://www.lysator.liu.se/c/ten-commandments.html https://www.lysator.liu.se/c/ten-commandments.html
dooglius 5mo ago
The preceding comment indicates that the intent is to support other compilers. I think a better approach is to define __glibc_attribute__ based on compiler support and to stick to that within glibc since there's no reason to think that another compiler's attributes have the same semantics as GNU C's.
- rurban 5mo ago
  That ship sailed already. You simply have to mimic gcc. Which is at least better than with MSVC, where they did everything differently, and only half of it.
  - account42 5mo ago
    Well in practice you have to mimic GCC except for Windows where you have to mimic MSVC.
    - rurban 5mo ago
      Not really. MSVC is too broken. I just mimic x86_64-w64-mingw32-gcc, which exists everywhere.
rwmj 5mo ago
MSVC support for C is fairly terrible. For the projects we write that are portable to Windows we insist you use GCC or Clang on Windows. No one has time to deal with the lack of even standard C1x/C2x features (never mind useful extensions like attribute cleanup). Surprised about FreeBSD. My experience is that porting Linux software is usually pretty easy as long as it's not using some Linux-only feature (io_uring for instance).
- jstimpfle 5mo ago
  What do you even miss, honestly works fine for me? In terms of platform APIs, I prefer the Windows ones on Windows anyway
  - drwu 5mo ago
    Complex numbers, for example. Also, C preprocessor expands macros differently on MSVC.
    - david2ndaccount 5mo ago
      Use the new standards-conformant preprocessor with `/Zc:preprocessor` https://learn.microsoft.com/en-us/cpp/build/reference/zc-preprocessor?view=msvc-170 https://learn.microsoft.com/en-us/cpp/build/reference/zc-pre...
    - jstimpfle 5mo ago
      Wasn't aware of preprocessor conformity issues, good to know!
- bigbadfeline 5mo ago
  > Surprised about FreeBSD. My experience is that porting Linux software is usually pretty easy as long as it's not using some Linux-only feature (io_uring for instance). I'm not sure why you're surprised, the parent of you comment clearly stated "on FreeBSD you often run into systemd dependencies or other non-posix behaviors" which means, software written for Linux often uses "Linux-only features" such as systemd and other non-posix dependencies that are foreign to the BSDs and traditional UNIX. Thus, it shouldn't be surprising that Linux software is hard to port to the BSDs. Linux used to be a pretty good UNIX, I'm not sure what it is now.
einpoklum 5mo ago
systemd is indeed the bane of Linux, and a pain in the ass for a lot of FOSS. Once the main distributions made it mandatory to install (not just the default, but mandatory) - we've started to see this sort of bifrucation of a lot more FOSS away from being standard-based and multi-platform to being Linux-specific. That said - I think a rule-of-thumb one can follow is that any inclusion of a file with a directory prefix, especially `<sys/whatever>`, needs a guarantee-of-availability in your build configuration phase, e.g. CMake `find_package()`, or or at least `check_include_file()` and such. That way, you might be more likely to fail to build, but at least you'll be telling the user "I expect these things to be present".
- jeltz 5mo ago
  No, systemd is not the bane of Linux. What existed before it was much worse. Upstart was a totally broken mess and almost all sysv init scripts contained several bugs. I don't like systemd but it is a lesser evil.
  - einpoklum 5mo ago
    systemd is not an init system; it _contains_ an init system. It is a huge swatch of the whole userspace of a Linux system up to shell or GUI sessions - and having an init system was just an excuse; and in fact, the systemd point brought up in the linked article is unrelated to init systems. There are quite a few init systems: The venerable sysvinit, runit, s6, openrc and others. You don't like upstart? Ok, choose another one, there are many. Here is a comparison table by the Gentoo folks: https://wiki.gentoo.org/wiki/Comparison_of_init_systems https://wiki.gentoo.org/wiki/Comparison_of_init_systems As for the claim of "almost all sysvinit scripts contained several bugs" - that's both hyperbole and false. Plus, you seem to be implying that systemd has not been troubled by bugs, which of course it has (and that does not disqualify it; the fundamental design and organizational nature as a project are the disqualifiers).
    - cestith 5mo ago
      The systemd init system is quite the Trojan horse, though. I prefer it greatly to SystemV init. Most of the rest of systemd varies from unremarkable to problematic in my opinion. One bright spot is systemd-networkd allows one to change quite a few things about interfaces in the way server automation platforms expect to work without doing a network restart. The workaround otherwise on, say, CentOS was always to write the new config file used by future restarts, also run CLI commands to update things in memory, and be sure to tell the service not to trigger a restart on the config file(s) changing. Otherwise if you’re doing something like streaming UDP video your own automation can become a reliability issue.
matheusmoreira 5mo ago
> One of my pet-peeves with C projects is that it's so often more or less "works on my machine" when written by Linux users (as a Windows and FreeBSD user it often hits you on both those platforms). Windows users singling out Linux users for not catering to their platform. How the times change... > you often run into systemd dependencies or other non-posix behaviors Not a problem. POSIX is irrelevant, systemd is great and we should all be using Linux to its fullest extent. Linux has great features and there is absolutely no reason not to use them all. Nobody complains about the fact BSDs have cool things like kqueue and unveil.
- neonz80 5mo ago
  > Windows users singling out Linux users for not catering to their platform. How the times change... In my experience this was a problem over 25 years ago when I developed for Solaris and other non-Linux operating systems.
  - benj111 5mo ago
    I think I may(?) have got into Linux 20+ years ago when I was trying to learn c and even the basic Hello World wouldn't work for me. So I suppose it does have a marketing benefit in that I now use Linux.
- whizzter 5mo ago
  > Windows users singling out Linux users for not catering to their platform. How the times change... This goes back to the days I was browsing freshmeat and saw some interesting command line tool or otherwise non-UI tool from some hopeful developer for something useful. Node had significant traction but didn't really blow up until it became really cross-platform. And perhaps is less of an issue these days since so many people use Mac's as their primary, so less Linux-isms survive once in context with osX. > Not a problem. POSIX is irrelevant, systemd is great and we should all be using Linux to its fullest extent. Linux has great features and there is absolutely no reason not to use them all. Nobody complains about the fact BSDs have cool things like kqueue and unveil. From following it over the year it was not entirely welcomed even in the linux community (and some of the security issues made one shudder). Mostly it's the monolithic nature that's makes it a questionable, is it Gnu/Linux these days or Systemd/Linux ? kqueue is just an api, just like epoll, io_uring or even iocp on windows. And yes, it's a special case for high-perf servers where posix becomes less relevant (and while I can appreciate some lower-perf fallback to be able to develop/port to another platform like a console I do see that some programs are inherently platform bound). I think one thing lost in my original comment was that I was often encountering things like this with "simple" CLI tools or lower level format libraries, and honestly projects like that also had a tendency to break over time without updates as they often relied on specific versions of libraries the maintainers had installed via Linux package managers, in the same fashion as npm has caused churn in the JS community. (npm at least has version pinning so old cli tools can often be run as long as node hasn't deprecated api's).
dgrunwald 5mo ago
In our compiler (in a code analysis tool), we have #pragma immutable_macro __attribute__ After this pragma, any attempt to #define/#undef the macro "__attribute__" will be silently ignored. This lets us (or our customers) bypass such stupidity in library headers. It's also often useful to replace broken macros with working versions.

formerly_proven 5mo ago

For a bunch of software categories there isn't really much point to support Windows at all these days. We've had "developed for unix, ported to Windows" software for a long time and it often doesn't work that well, because the agreement even for fairly basic stuff is not that large between the two.

zephen 5mo ago
There's portability between systems, which as you note, has ever-diminishing returns. Then there's portability between compilers, which, as the article notes, glibc is also completely hostile to (except for anointed compilers) for no good reason whatsoever.
- account42 5mo ago
  > which, as the article notes, glibc is also completely hostile to This is neither true nor claimed by the article.
  - zephen 5mo ago
    The article specifically states "If you aren't gcc, clang, or tcc, tough luck." It doesn't work. For no good reason. Because there are a few anointed compilers. That it wasn't on purpose doesn't make it not hostile.
deleted 5mo ago
[deleted]
jdw64 5mo ago
in Asia, and over here, Windows is the de facto standard while Linux is actually a poor option. Almost all of the infrastructure is written for Windows, so the second you switch to Linux, you're fighting an uphill battle just to do basic tasks. Seeing this makes you realize that our worldview is entirely shaped by the ecosystem we live in
whizzter 5mo ago
1: My point isn't "developer on unix, ported to Windows", it's "developed on linux, maybe works elsewhere". 2: You could easily compile Samba yourself for FreeBSD in the past, last time I tried a new version it broke in what I remember being due to linux-isms (yes there is ports, but being reliant on older versions if ports maintainers can't keep up isn't a good thing). 3: The only "fairly basic" stuff that's hugely different is mostly the absence/reliance on shell-scripts (when building), but that has little to do with the actual code function (Personally I often used Node scripts in those scenarios, Python scripts would probably be an improvement since there's no reason it couldn't be everywhere). I used to use Tremor to decode Ogg audio (no UI needs, just binary data in, arrays of primitive values in audio buffers out), early versions were easy to compile under Windows but building later versions were buried in shell scripts generating headers,etc for no real good reason (maybe to help port when working on a Linux workstation to other embedded devices but made the code less easily compilable by default), the core functionality only really needed a C compiler as early versions showed. I can agree that something with advanced UI's like Blender (that relies on GL/3d rendering for UI) might not be easily portable, but when algortihm libraries often requires heavy reworking it's not a good thing (Here I think Github has helped since people has had an easier time to contribute, it's a sad thing that people are moving away due to the AI-crap). In the end, it's not about _actual_ differences but more of a superiority complex of Linux users that is the main roadblock.
- rootnod3 5mo ago
  Exactly, the amount of patches needed in many FreeBSD or other BSD ports just to appease the Linux-centricity is bonkers. And many times the changes aren't even that grave.
- matheusmoreira 5mo ago
  Superiority complex? How many times have we been told that we're entitled freeloaders for expecting Linux compatibility work from others? Insulted by people who use dominant platforms that get all the commercial support while we get literally nothing? Reduced to reverse engineering stuff with no documentation and zero help? Pretty wild to watch this unfold. Now that Linux is finally coming out ahead, as it should, because people are finally writing software for it... Suddenly we're the bullies.

BadBadJellyBean 5mo ago

If it is an open source project then that is quite alright with me. An open source author doesn't need to support all platforms. Only those they care about. If someone else wants support for another platform they have the source.

whizzter 5mo ago
Yeah, I think I did miss mentioning that my comment was more weighted on simpler cli tools or library projects (file format readers,etc). I don't expect anyone writing GUI tools or more high-perf servers to spend their time porting to other platforms (trying to compile GTK on Windows wasn't for the faint of heart).

kps 5mo ago

>One of my pet-peeves with C projects is that it's so often more or less "works on my machine" “All the world's a VAX” https://groups.google.com/g/comp.lang.c/c/CYgWkWdWCcQ/m/thMt3RfByAgJ?pli=1 https://groups.google.com/g/comp.lang.c/c/CYgWkWdWCcQ/m/thMt... https://www.lysator.liu.se/c/ten-commandments.html https://www.lysator.liu.se/c/ten-commandments.html

dooglius 5mo ago

The preceding comment indicates that the intent is to support other compilers. I think a better approach is to define __glibc_attribute__ based on compiler support and to stick to that within glibc since there's no reason to think that another compiler's attributes have the same semantics as GNU C's.

rurban 5mo ago
That ship sailed already. You simply have to mimic gcc. Which is at least better than with MSVC, where they did everything differently, and only half of it.
- account42 5mo ago
  Well in practice you have to mimic GCC except for Windows where you have to mimic MSVC.
  - rurban 5mo ago
    Not really. MSVC is too broken. I just mimic x86_64-w64-mingw32-gcc, which exists everywhere.

rwmj 5mo ago

MSVC support for C is fairly terrible. For the projects we write that are portable to Windows we insist you use GCC or Clang on Windows. No one has time to deal with the lack of even standard C1x/C2x features (never mind useful extensions like attribute cleanup). Surprised about FreeBSD. My experience is that porting Linux software is usually pretty easy as long as it's not using some Linux-only feature (io_uring for instance).

jstimpfle 5mo ago
What do you even miss, honestly works fine for me? In terms of platform APIs, I prefer the Windows ones on Windows anyway
- drwu 5mo ago
  Complex numbers, for example. Also, C preprocessor expands macros differently on MSVC.
  - david2ndaccount 5mo ago
    Use the new standards-conformant preprocessor with `/Zc:preprocessor` https://learn.microsoft.com/en-us/cpp/build/reference/zc-preprocessor?view=msvc-170 https://learn.microsoft.com/en-us/cpp/build/reference/zc-pre...
  - jstimpfle 5mo ago
    Wasn't aware of preprocessor conformity issues, good to know!
bigbadfeline 5mo ago
> Surprised about FreeBSD. My experience is that porting Linux software is usually pretty easy as long as it's not using some Linux-only feature (io_uring for instance). I'm not sure why you're surprised, the parent of you comment clearly stated "on FreeBSD you often run into systemd dependencies or other non-posix behaviors" which means, software written for Linux often uses "Linux-only features" such as systemd and other non-posix dependencies that are foreign to the BSDs and traditional UNIX. Thus, it shouldn't be surprising that Linux software is hard to port to the BSDs. Linux used to be a pretty good UNIX, I'm not sure what it is now.

einpoklum 5mo ago

systemd is indeed the bane of Linux, and a pain in the ass for a lot of FOSS. Once the main distributions made it mandatory to install (not just the default, but mandatory) - we've started to see this sort of bifrucation of a lot more FOSS away from being standard-based and multi-platform to being Linux-specific. That said - I think a rule-of-thumb one can follow is that any inclusion of a file with a directory prefix, especially `<sys/whatever>`, needs a guarantee-of-availability in your build configuration phase, e.g. CMake `find_package()`, or or at least `check_include_file()` and such. That way, you might be more likely to fail to build, but at least you'll be telling the user "I expect these things to be present".

jeltz 5mo ago
No, systemd is not the bane of Linux. What existed before it was much worse. Upstart was a totally broken mess and almost all sysv init scripts contained several bugs. I don't like systemd but it is a lesser evil.
- einpoklum 5mo ago
  systemd is not an init system; it _contains_ an init system. It is a huge swatch of the whole userspace of a Linux system up to shell or GUI sessions - and having an init system was just an excuse; and in fact, the systemd point brought up in the linked article is unrelated to init systems. There are quite a few init systems: The venerable sysvinit, runit, s6, openrc and others. You don't like upstart? Ok, choose another one, there are many. Here is a comparison table by the Gentoo folks: https://wiki.gentoo.org/wiki/Comparison_of_init_systems https://wiki.gentoo.org/wiki/Comparison_of_init_systems As for the claim of "almost all sysvinit scripts contained several bugs" - that's both hyperbole and false. Plus, you seem to be implying that systemd has not been troubled by bugs, which of course it has (and that does not disqualify it; the fundamental design and organizational nature as a project are the disqualifiers).
  - cestith 5mo ago
    The systemd init system is quite the Trojan horse, though. I prefer it greatly to SystemV init. Most of the rest of systemd varies from unremarkable to problematic in my opinion. One bright spot is systemd-networkd allows one to change quite a few things about interfaces in the way server automation platforms expect to work without doing a network restart. The workaround otherwise on, say, CentOS was always to write the new config file used by future restarts, also run CLI commands to update things in memory, and be sure to tell the service not to trigger a restart on the config file(s) changing. Otherwise if you’re doing something like streaming UDP video your own automation can become a reliability issue.

matheusmoreira 5mo ago

> One of my pet-peeves with C projects is that it's so often more or less "works on my machine" when written by Linux users (as a Windows and FreeBSD user it often hits you on both those platforms). Windows users singling out Linux users for not catering to their platform. How the times change... > you often run into systemd dependencies or other non-posix behaviors Not a problem. POSIX is irrelevant, systemd is great and we should all be using Linux to its fullest extent. Linux has great features and there is absolutely no reason not to use them all. Nobody complains about the fact BSDs have cool things like kqueue and unveil.

neonz80 5mo ago
> Windows users singling out Linux users for not catering to their platform. How the times change... In my experience this was a problem over 25 years ago when I developed for Solaris and other non-Linux operating systems.
- benj111 5mo ago
  I think I may(?) have got into Linux 20+ years ago when I was trying to learn c and even the basic Hello World wouldn't work for me. So I suppose it does have a marketing benefit in that I now use Linux.
whizzter 5mo ago
> Windows users singling out Linux users for not catering to their platform. How the times change... This goes back to the days I was browsing freshmeat and saw some interesting command line tool or otherwise non-UI tool from some hopeful developer for something useful. Node had significant traction but didn't really blow up until it became really cross-platform. And perhaps is less of an issue these days since so many people use Mac's as their primary, so less Linux-isms survive once in context with osX. > Not a problem. POSIX is irrelevant, systemd is great and we should all be using Linux to its fullest extent. Linux has great features and there is absolutely no reason not to use them all. Nobody complains about the fact BSDs have cool things like kqueue and unveil. From following it over the year it was not entirely welcomed even in the linux community (and some of the security issues made one shudder). Mostly it's the monolithic nature that's makes it a questionable, is it Gnu/Linux these days or Systemd/Linux ? kqueue is just an api, just like epoll, io_uring or even iocp on windows. And yes, it's a special case for high-perf servers where posix becomes less relevant (and while I can appreciate some lower-perf fallback to be able to develop/port to another platform like a console I do see that some programs are inherently platform bound). I think one thing lost in my original comment was that I was often encountering things like this with "simple" CLI tools or lower level format libraries, and honestly projects like that also had a tendency to break over time without updates as they often relied on specific versions of libraries the maintainers had installed via Linux package managers, in the same fashion as npm has caused churn in the JS community. (npm at least has version pinning so old cli tools can often be run as long as node hasn't deprecated api's).

dgrunwald 5mo ago

In our compiler (in a code analysis tool), we have #pragma immutable_macro __attribute__ After this pragma, any attempt to #define/#undef the macro "__attribute__" will be silently ignored. This lets us (or our customers) bypass such stupidity in library headers. It's also often useful to replace broken macros with working versions.