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Fixed in 2020.2.X
Fixed in 2019.3.X, 2020.1.X
Votes
4
Found in
2019.3.0a6
2019.3.0f6
2020.1
Issue ID
1218247
Regression
Yes
[Linux] DllNotFoundException error when using DeflateStream if there is no libMonoPosixHelper.so at /usr/lib
How to reproduce:
1. Open user's attached project (Libmonoposixissue.zip)
2. Make sure 'SampleScene' is open and enter Play mode
Expected result: Deflated string array length is printed to the console
Actual result: "DllNotFoundException: libMonoPosixHelper.so" is thrown to the console
Reproducible with: 2019.3.0a6, 2019.3.1f1, 2020.1.0a23
Not reproducible with: 2017.4.36f1, 2018.4.17f1, 2019.3.0a5
Regression from 2019.3.0a5 to 2019.3.0a6
Full error:
DllNotFoundException: libMonoPosixHelper.so
System.IO.Compression.DeflateStreamNative.Create (System.IO.Stream compressedStream, System.IO.Compression.CompressionMode mode, System.Boolean gzip) (at <e304493dc8584f28b068435a506526d3>:0)
System.IO.Compression.DeflateStream..ctor (System.IO.Stream compressedStream, System.IO.Compression.CompressionMode mode, System.Boolean leaveOpen, System.Boolean gzip) (at <e304493dc8584f28b068435a506526d3>:0)
System.IO.Compression.DeflateStream..ctor (System.IO.Stream stream, System.IO.Compression.CompressionMode mode) (at <e304493dc8584f28b068435a506526d3>:0)
(wrapper remoting-invoke-with-check) System.IO.Compression.DeflateStream..ctor(System.IO.Stream,System.IO.Compression.CompressionMode)
DeflateString.Start () (at Assets/Runtime/DeflateString.cs:16)
Notes:
- The file when looking at it from a non-Unity context, seems to be a part of 'mono-devel' package, installing it should fix the error.
Comments (5)
-
jesusluvsyooh
Aug 15, 2025 18:47
This issue is back, libMonoPosixHelper.dylib is included, but the codes looking for it in wrong location. (regarding using System.IO.Compression; and DeflateStream)
Root/libMonoPosixHelper.dylib (included, but says cannot be found)
Root/Data/Managed/libMonoPosixHelper.dylib (copy it here, now it can be found)Dedicated Server build, happens on Unity 2022, and 6000.
-
jesusluvsyooh
Aug 15, 2025 18:47
This issue is back, libMonoPosixHelper.dylib is included, but the codes looking for it in wrong location. (regarding using System.IO.Compression; and DeflateStream)
Root/libMonoPosixHelper.dylib (included, but says cannot be found)
Root/Data/Managed/libMonoPosixHelper.dylib (copy it here, now it can be found)Dedicated Server build, happens on Unity 2022, and 6000.
-
Edwin_Lee
Mar 21, 2023 14:29
[unity2021.3.18f1c1 build mac and liunx dedicated server]
Unknown "EdwindeMacBook-Pro.local" DllNotFoundException: libMonoPosixHelper.dylib assembly:<unknown assembly> type:<unknown type> member:(null)
at (wrapper managed-to-native) System.IO.Compression.DeflateStreamNative.CreateZStream(System.IO.Compression.CompressionMode,bool,System.IO.Compression.DeflateStreamNative/UnmanagedReadOrWrite,intptr)
at System.IO.Compression.DeflateStreamNative.Create (System.IO.Stream compressedStream, System.IO.Compression.CompressionMode mode, System.Boolean gzip) [0x0004a] in <9d6889174a4d48a4aa2a3e29a67e35d4>:0
at System.IO.Compression.DeflateStream..ctor (System.IO.Stream compressedStream, System.IO.Compression.CompressionMode mode, System.Boolean leaveOpen, System.Boolean gzip) [0x0002d] in <9d6889174a4d48a4aa2a3e29a67e35d4>:0
at System.IO.Compression.DeflateStream..ctor (System.IO.Stream stream, System.IO.Compression.CompressionMode mode) [0x00000] in <9d6889174a4d48a4aa2a3e29a67e35d4>:0
at (wrapper remoting-invoke-with-check) System.IO.Compression.DeflateStream..ctor(System.IO.Stream,System.IO.Compression.CompressionMode)
at SuperNet.Netcode.Compress.CompressorDeflate.Decompress (System.ArraySegment`1[T] input, System.Byte[]& output, System.Int32 offset) [0x00077] in /Users/edwinlee/Desktop/Development/UnityProjects/ArouseBlockchain_New/Assets/SuperNet/Scripts/Netcode/Compress/CompressorDeflate.cs:94
at SuperNet.Netcode.Transport.Peer.OnReceiveAsync (System.Byte[] buffer, System.Int32 length) [0x0109e] in /Users/edwinlee/Desktop/Development/UnityProjects/ArouseBlockchain_New/Assets/SuperNet/Scripts/Netcode/Transport/Peer.cs:1387
UnityEngine.DebugLogHandler:Internal_LogException(Exception, Object)
UnityEngine.DebugLogHandler:LogException(Exception, Object)
UnityEngine.Logger:LogException(Exception, Object)
UnityEngine.Debug:LogException(Exception)
ArouseBlockchain.P2PNet.ANetworkHost:SuperNet.Netcode.Transport.IPeerListener.OnPeerException(Peer, Exception) (at /Users/edwinlee/Desktop/Development/UnityProjects/ArouseBlockchain_New/Assets/ArouseBlockchain/Scripts/P2PNet/ANetworkHost.cs:885)
SuperNet.Netcode.Transport.<OnReceiveAsync>d__77:MoveNext() (at /Users/edwinlee/Desktop/Development/UnityProjects/ArouseBlockchain_New/Assets/SuperNet/Scripts/Netcode/Transport/Peer.cs:1413)
System.Runtime.CompilerServices.AsyncTaskMethodBuilder:Start(<OnReceiveAsync>d__77&)
SuperNet.Netcode.Transport.Peer:OnReceiveAsync(Byte[], Int32)
SuperNet.Netcode.Transport.<Receive>d__58:MoveNext() (at /Users/edwinlee/Desktop/Development/UnityProjects/ArouseBlockchain_New/Assets/SuperNet/Scripts/Netcode/Transport/Host.cs:958)
System.Runtime.CompilerServices.AsyncTaskMethodBuilder:Start(<Receive>d__58&)
SuperNet.Netcode.Transport.Host:Receive(IPEndPoint, Byte[], Int32)
SuperNet.Netcode.Transport.<>c__DisplayClass56_1:<ReceiveWorkerAsync>b__0() (at /Users/edwinlee/Desktop/Development/UnityProjects/ArouseBlockchain_New/Assets/SuperNet/Scripts/Netcode/Transport/Host.cs:884)
System.Threading.Tasks.Task`1:InnerInvoke()
System.Threading.Tasks.Task:Execute()
System.Threading.Tasks.Task:ExecutionContextCallback(Object)
System.Threading.ExecutionContext:RunInternal(ExecutionContext, ContextCallback, Object, Boolean)
System.Threading.ExecutionContext:Run(ExecutionContext, ContextCallback, Object, Boolean)
System.Threading.Tasks.Task:ExecuteWithThreadLocal(Task&)
System.Threading.Tasks.Task:ExecuteEntry(Boolean)
System.Threading.Tasks.Task:System.Threading.IThreadPoolWorkItem.ExecuteWorkItem()
System.Threading.ThreadPoolWorkQueue:Dispatch()
System.Threading._ThreadPoolWaitCallback:PerformWaitCallback()(Filename: /Users/edwinlee/Desktop/Development/UnityProjects/ArouseBlockchain_New/Assets/ArouseBlockchain/Scripts/P2PNet/ANetworkHost.cs Line: 885)
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Edwin_Lee
Mar 21, 2023 14:13
Hello, I showed up again at unity2021.3.18f1c1 build mac and liunx dedicated server! Very anxious
-
Rs
Mar 13, 2020 21:38
Having this issue in Unity 2019.3.3f1 under Debian Stretch, Mate desktop, NVidia 1080 with proprietary drivers.
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