Compatibility no NO

Compatibility

ASF is a C# application that is running on .NET Core platform. This means that ASF is not compiled directly into machine code that is running on your CPU, but into CIL that requires a CIL-compatible runtime for executing it.

This approach has gigantic amount of advantages, as CIL is platform-independent, which is why ASF can run natively on many available OSes, especially Windows, Linux and OS X. There is not only no emulation needed, but also support for all platform-related and hardware-related optimizations, such as CPU SSE instructions. Thanks to that, ASF can achieve superior performance and optimization, while still offering a perfect compatibility and reliability.

This also means that ASF has no specific OS requirement, because it requires working runtime on that OS and not OS itself. As long as that runtime is executing ASF code properly, it does not matter whether underlying OS is Windows, Linux, OS X, BSD, Sony Playstation 4, Nintendo Wii or your toaster - as long as there is .NET Core for it, there is ASF for it.

However, regardless of where you run ASF, you must ensure that your target platform has .NET Core prerequisites installed. Those are low-level libraries required for proper runtime functionality and absolutely core for ASF to work in the first place. Very likely you can have some of them (or even all) already installed.

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ASF packaging

ASF comes in 2 main flavours - generic package and OS-specific. Functionality-wise both packages are exactly the same, they're both also capable of automatically updating themselves. The only difference between them is whether or not ASF generic package also comes with OS-specific runtime to power it.

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Generic

Generic package is platform-agnostic build that doesn't include any machine-specific code. This setup requires from you to have .NET Core runtime already installed on your OS in appropriate version. We all know how troublesome it is to keep dependencies up-to-date, therefore this package is here mainly for people that already use .NET Core and don't want to duplicate their runtime solely for ASF if they can make use of what they have installed already. Generic package also allows you to run ASF anywhere where you can obtain working implementation of .NET Core runtime, regardless if there exists OS-specific ASF build for it, or not.

It's not recommended to use generic flavour if you're casual or even advanced user that just wants to make ASF work and not dig into .NET Core technical details. In other words - if you know what this is, you can use it, otherwise it's much better to use OS-specific package explained below.

.NET Framework package

In addition to generic package mentioned above, there is also generic-netf package which is built on top of .NET Framework (and not .NET Core). This package is a legacy variant that provides missing compatibility known from ASF V2 times, and can be run e.g. with Mono, while .NET Core generic package can't as of today.

In general you should avoid this package as much as possible, as majority of operating systems and setups are perfectly (and much better) supported with generic package mentioned above. In fact, this package makes sense to be used only on platforms that lack working .NET Core runtime, while having working Mono implementation. An example of such platform would be linux-x86 that didn't receive working .NET Core runtime as of today.

As the time goes on with more platforms being supported by .NET Core and less compatibility between .NET Framework and .NET Core, generic-netf package will be entirely replaced with generic one in the future. Please refrain from using it if you can use any .NET Core package instead, as generic-netf is missing a lot of functionality and compatibility compared to .NET Core versions, and it'll be only less functional as the time goes on.

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OS-specific

OS-specific package, apart from managed code included in generic package, also includes native code for given platform. In other words, OS-specific package already includes proper .NET Core runtime inside, which allows you to entirely skip the whole installation mess and just launch ASF directly. OS-specific package, as you can guess from the name, is OS-specific and every OS requires its own version - for example Windows requires PE32+ ArchiSteamFarm.exe binary while Linux works with Unix ELF ArchiSteamFarm binary. As you might know, those two types are not compatible with each other.

ASF is currently available in following OS-specific variants:

• win-x64 works on 64-bit Windows OSes. This includes Windows 7 (SP1+), 8, 8.1, 10, Server 2008 R2 (SP1+), 2012, 2012 R2, 2016, as well as future versions.
• linux-arm works on 32-bit ARM-based (ARMv7+) Linux OSes. This includes especially Raspberry Pi 2 & 3 with all glibc-based Linux OSes available for them, in current and future versions. This variant will not work with older ARM architectures, such as ARMv6 found in Raspberry Pi 0 & 1.
• linux-x64 works on 64-bit glibc-based Linux OSes. This includes Alpine, CentOS/Fedora/RHEL, Debian/Ubuntu/Linux Mint, OpenSUSE/SLES and many other ones, including their derivatives, in current and future versions.
• osx-x64 works on 64-bit OS X OSes. This includes 10.12, as well as future versions.

Of course, even if you don't have OS-specific package available for your OS-architecture combination, you can always install appropriate .NET Core runtime yourself and run generic ASF flavour, which is also the main reason why it exists in the first place. Generic ASF build is platform-agnostic and will run on any platform that has a working .NET Core runtime. This is important to note - ASF requires .NET Core runtime, not some specific OS or architecture. For example, if you're running 32-bit Windows then despite of no dedicated win-x86 ASF version, you can still install .NET Core SDK in win-x86 version and run generic ASF just fine. We simply can't target every OS-architecture combination that exists and is used by somebody, so we have to draw a line somewhere. x86 is a good example of that line, as it's obsolete architecture since at least 2004.

For a complete list of all supported platforms and OSes by .NET Core 2.1, visit release notes.

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Runtime requirements

If you're using OS-specific package then you don't need to worry about runtime requirements, because ASF always ships with required and up-to-date runtime that will work properly as long as you have .NET Core prerequisites installed and up-to-date.

However, if you're trying to run generic ASF package then you must ensure that your .NET Core runtime supports platform required by ASF.

ASF as a program is targetting .NET Core 2.1 (netcoreapp2.1) right now, but it might target newer platform in the future. netcoreapp2.1 is supported since 2.1.300 SDK (2.1.0 runtime), although we recommend using latest SDK available for your machine.

If in doubt, check what our continuous integration uses for compiling and deploying ASF releases on GitHub. You can find dotnet --info output on top of each build.

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Issues and solutions

Debian Jessie upgrade

If you upgraded from Debian 8 Jessie (or older) to Debian 9 Stretch, ensure that you don't have libssl1.0.0 package, for example with apt-get purge libssl1.0.0. Otherwise, you might run into a segfault. This package is obsolete and doesn't exist by definition, neither is possible to install on clean Debian 9 setups, the only way to run into this issue is upgrading from Debian 8 or older - dotnet/corefx #8951. If you have some other packages depending on that outdated libssl version then you should either upgrade them, or get rid of them - not only because of this issue, but also because they're based on obsolete library in the first place.

Invalid machine certs with ASF V3.2+

Under linux (only), you might get specific issue related to SSL certificates provided by your machine. This will show as an exception below:

System.Net.Http.HttpRequestException: The SSL connection could not be established, see inner exception. ---> Interop+Crypto+OpenSslCryptographicException: error:2006D002:BIO routines:BIO_new_file:system lib
   at Interop.Crypto.CheckValidOpenSslHandle(SafeHandle handle)

This issue is most likely caused by some of the certificates not being possible to be read. This could be because of insufficient permissions (as a test you can check if ASF works under root user) or other issues populating invalid certificate files.

The current workaround depends on the root issue. On clean setups (e.g. Debian), this should never happen as there should be no invalid/sensitive certificates in the store, so the issue considers only people that are most likely having other certs for other purposes (e.g. VPN or websites) that ASF has no access to read. You can consider either giving proper permissions to ASF user (such as ensuring that all SSL certificates in /etc/pki and /etc/ssl have at least 644 global read permission), running ASF under root, or moving sensitive certificates somewhere else so ASF does not attempt to read them during initialization.

This issue is supposed to be fixed with next .NET Core 2.1.1 servicing release, therefore the workarounds presented above shouldn't be required anymore in near future.

Reference: dotnet/corefx #29942.

.NET Core runtime picking wrong libcurl.so library

If you have both libcurl.so.3 and libcurl.so.4 on your system then .NET Core might decide to pick second one, which will lead to ASF crash the moment it'll try to initialize its http client.

OnUnhandledException() System.TypeInitializationException: The type initializer for 'System.Net.Http.CurlHandler' threw an exception. ---> System.TypeInitializationException: The type initializer for 'Http' threw an exception. ---> System.TypeInitializationException: The type initializer for 'HttpInitializer' threw an exception. ---> System.DllNotFoundException: Unable to load DLL 'System.Net.Http.Native': The specified module or one of its dependencies could not be found.

If you stumble upon the issue above, then you might need to manually tell .NET Core runtime to pick up proper library in this case. Locate libcurl.so.3 on your system and add it to LD_PRELOAD before starting ASF:

LD_PRELOAD=/usr/lib/libcurl.so.3 ./ArchiSteamFarm

This should hopefully solve the issue, assuming your libcurl.so.3 is working properly.