IM example on linux

Examples/SwiftSerialIM/Package.swift

@@ -0,0 +1,8 @@
+import PackageDescription
+
+let package = Package(
+    name: "SwiftSerialIM",
+    dependencies: [
+    	.Package(url: "https://github.com/yeokm1/SwiftSerial.git", majorVersion: 0)
+	]
+)

Examples/SwiftSerialIM/Sources/main.swift

@@ -0,0 +1,115 @@
+import Foundation
+import SwiftSerial
+
+
+let arguments = CommandLine.arguments
+guard arguments.count >= 2 else {
+    print("Need serial port name, e.g. /dev/ttyUSB0 as the first argument.")
+    exit(1)
+}
+
+print("Connect a null modem serial cable between two machines before you continue to use this program")
+
+let portName = arguments[1]
+let serialPort: SerialPort = SerialPort(path: portName)
+
+var myturn = true
+
+
+func getKeyPress () -> UnicodeScalar {
+    let valueRead: Int = Int(getchar())
+
+    guard let charRead = UnicodeScalar(valueRead) else{
+        return UnicodeScalar("")!
+    }
+
+    return charRead
+}
+
+func printToScreenFrom(myself: Bool, characterToPrint: UnicodeScalar){
+
+    if(myturn && !myself){
+        myturn = false
+        print("\nOther: ", terminator:"")
+    } else if (!myturn && myself){
+        myturn = true
+        print("\nMe: ", terminator:"")
+    }
+
+    print(characterToPrint, terminator:"")
+}
+
+
+
+do {
+
+    print("Attempting to open port: \(portName)")
+    try serialPort.openPort()
+    print("Serial port \(portName) opened successfully.")
+    defer {
+        serialPort.closePort()
+        print("Port Closed")
+    }
+
+    serialPort.setSettings(receiveRate: .baud9600,
+                           transmitRate: .baud9600,
+                           minimumBytesToRead: 1)
+
+    
+    /* These prepares the stdin so we can getchar() without echoing */
+    // Set up the control structure
+    var settings = termios()
+
+    // Get options structure for stdin
+    tcgetattr(STDIN_FILENO, &settings)
+
+    //Turn off ICANON and ECHO
+    settings.c_lflag &= ~tcflag_t(ICANON | ECHO)
+
+    tcsetattr(STDIN_FILENO, TCSANOW, &settings)
+
+
+
+
+    //Turn off output buffering if not multiple threads will have problems printing
+    setbuf(stdout, nil);
+
+
+    //Run the serial port reading function in another thread
+    var readingThread = pthread_t()
+
+    let pthreadFunc: @convention(c) (UnsafeMutableRawPointer?) -> UnsafeMutableRawPointer? = {
+        observer in
+        while true{
+            do{
+                var readCharacter = try serialPort.readChar()
+                printToScreenFrom(myself: false, characterToPrint: readCharacter)
+            } catch {
+                print("Error: \(error)")
+            }
+        }  
+
+    }
+
+    pthread_create(&readingThread, nil, pthreadFunc, nil)
+
+
+
+    print("\nReady to send and receive messages in realtime!")
+    print("\nMe: ", terminator:"")
+
+
+    while true {
+        var enteredKey = getKeyPress()
+        printToScreenFrom(myself: true, characterToPrint: enteredKey)
+        var _ = try serialPort.writeChar(enteredKey)
+    }
+
+
+} catch PortError.failedToOpen {
+    print("Serial port \(portName) failed to open. You might need root permissions.")
+} catch {
+    print("Error: \(error)")
+}
+
+