Modern syslog client for .NET with dual logging (local libc + remote UDP) and RFC 5424 support. Fork of jitbit/SyslogCore with critical improvements.

// 1. One-time initialization
cSyslogClient.Init(appName: "MyApp",remoteServer: "10.0.0.1" // Optional);

// 2. Logging (auto module detection)
cSyslogClient.Write("Payment processed", SyslogLevel.Info);

// 3. Graceful shutdown
cSyslogClient.Shutdown();

• Dual logging: Local (libc) + Remote (UDP RFC 5424)

• Structured messages: Timestamps, hostnames, priority levels

• Auto caller detection: [CallerMemberName] integration

• Resource-safe: Proper GCHandle and UdpClient disposal

• Zero dependencies: Single C# file (~150 LOC)

The original library was limited to local syslog. We added:

🚀 Remote syslog server support

📡 RFC 5424 compliance

🛡️ Safer resource management

🔍 Automatic caller module tracking

ASP.NET Core Integration

var builder = WebApplication.CreateBuilder(args);
var app = builder.Build();

cSyslogClient.Init("WebApp", "192.168.113.100");

app.Lifetime.ApplicationStopping.Register(() => 
{
    cSyslogClient.Write("Shutting down...");
    cSyslogClient.Shutdown();
});

app.MapGet("/", () => {
    cSyslogClient.Write("Homepage visited"); // Auto-detects "[GET] /" as module 
    return "Hello World";
});

cSyslogClient.Init(
    appName: "Backend",
    remoteServer: "10.0.0.1",  // UDP target
    remotePort: 8514,          // Custom port
    customHostName: "server-1" // Override hostname
);

2025-06-25T13:31:41.190245+03:00 dev69-u lk[206841]: [INFO] main: startup v0.2.1.0
2025-06-25T13:50:40.203339+03:00 dev69-u be[207439]: [INFO] main: startup v2.0.0.0
2025-06-25T13:57:50.985781+03:00 dev69-u be[207439]: [INFO] main(): shutdown
2025-06-25T13:57:51.513765+03:00 dev69-u be[207668]: [INFO] main: startup v2.0.0.0
2025-06-25T13:58:16.690086+03:00 dev69-u lk[206841]: [INFO] lk-files: Test from filesController
2025-06-25T13:58:23.113230+03:00 dev69-u be[207668]: [INFO] GetFileName: File report.pdf uploaded to caller

To direct logs to a dedicated file instead of /var/log/syslog, use Linux's local facilities (local0 through local7). Example for local0: Create rsyslog config (/etc/rsyslog.d/20-myapp.conf):

# Logs with facility=local0 to /var/log/myapp.log
local0.*    /var/log/myapp.log
& stop  # Prevent duplicate logging

This code uses Local0 by default. You can change it in:

// In LibC.openlog() call:
LibC.openlog(..., facility: 16 << 3);  // 16=local0, 17=local1, etc.

For high-throughput scenarios:

• Consider batching UDP messages

• Future upgrade path to LibraryImport (AOT support)

• Async logging possible via _udpClient.SendAsync

• Original credits: Jitbit
• Enhancements by: ish-1313
• License: MIT (same as original)