This is to fix running on Ubuntu 22x

[johnml1135]

• they don't have libdl.so - but only libdl.so.2
• see https://stackoverflow.com/questions/75855053/how-to-address-crash-due-to-missing-libdl-so-on-ubuntu-22

This work is untested

---

This change is 

[johnml1135]

I came across this when developing docker images for machine.py which uses SIL.WritingSystems. It will not initialize in Ubuntu 22 containers.

The error was:

machine-engine-cntr   |       System.DllNotFoundException: Unable to load shared library 'libdl.so' or one of its dependencies. In order to help diagnose loading problems, consider setting the LD_DEBUG environment variable: liblibdl.so: cannot open shared object file: No such file or directory
machine-engine-cntr   |          at Icu.NativeMethods.dlopen(String file, Int32 mode)
machine-engine-cntr   |          at Icu.NativeMethods.GetIcuLibHandle(String basename, Int32 icuVersion)
machine-engine-cntr   |          at Icu.NativeMethods.LoadIcuLibrary(String libraryName)
machine-engine-cntr   |          at Icu.NativeMethods.get_IcuCommonLibHandle()
machine-engine-cntr   |          at Icu.NativeMethods.u_getUnicodeVersion(VersionInfo& versionArray)
machine-engine-cntr   |          at Icu.Wrapper.get_UnicodeVersion()
machine-engine-cntr   |          at SIL.WritingSystems.Sldr.InitializeGetUnicodeCategoryBasedOnIcu()
machine-engine-cntr   |          at SIL.WritingSystems.Sldr.Initialize(Boolean offlineMode, String sldrCachePath, DateTime embeddedAllTagsTime)
machine-engine-cntr   |          at SIL.WritingSystems.Sldr.Initialize(Boolean offlineMode, String sldrCachePath)
machine-engine-cntr   |          at SIL.WritingSystems.Sldr.Initialize(Boolean offlineMode)
machine-engine-cntr   |          at SIL.Machine.AspNetCore.Services.ClearMLService..ctor(HttpClient httpClient, IOptionsMonitor`1 options, ILogger`1 logger, IClearMLAuthenticationService clearMLAuthService) in /home/johnml1135/repos/machine/src/SIL.Machine.AspNetCore/Services/ClearMLService.cs:line 29

[lyonsil]

In ICU.net, this was fixed between version 2.8.1 and 2.9.0 to make the icu.net.dll.config file work properly. The solution that ICU.net took will work on Macs, too, so it is something to consider if support beyond Linux is needed.

[ermshiperete]

I came across this when developing docker images for machine.py which uses SIL.WritingSystems. It will not initialize in Ubuntu 22 containers.

That's a slightly different error which won't be fixed by this PR. The most likely reason is that the icu.net.dll.config file is missing which needs to exist next to icu.net.dll. And if you're running .NET Core 3.x or .NET 5+ you'll need icu.net 2.9+.

[ermshiperete]

LGTM, but can you please add a line to CHANGELOG.md? Thanks!

[johnml1135]

Added comment to changelog - I believe in the right format.