Added work from my other class repositories before deletion

OSU Coursework/CS 344 - Operating Systems I/Assignment 4 - OTP/reference/client.c

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+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <netdb.h> 
+
+void error(const char *msg) { perror(msg); exit(0); } // Error function used for reporting issues
+
+int main(int argc, char *argv[])
+{
+	int socketFD, portNumber, charsWritten, charsRead;
+	struct sockaddr_in serverAddress;
+	struct hostent* serverHostInfo;
+	char buffer[256];
+    
+	if (argc < 3) { fprintf(stderr,"USAGE: %s hostname port\n", argv[0]); exit(0); } // Check usage & args
+
+	// Set up the server address struct
+	memset((char*)&serverAddress, '\0', sizeof(serverAddress)); // Clear out the address struct
+	portNumber = atoi(argv[2]); // Get the port number, convert to an integer from a string
+	serverAddress.sin_family = AF_INET; // Create a network-capable socket
+	serverAddress.sin_port = htons(portNumber); // Store the port number
+	serverHostInfo = gethostbyname(argv[1]); // Convert the machine name into a special form of address
+	if (serverHostInfo == NULL) { fprintf(stderr, "CLIENT: ERROR, no such host\n"); exit(0); }
+	memcpy((char*)&serverAddress.sin_addr.s_addr, (char*)serverHostInfo->h_addr, serverHostInfo->h_length); // Copy in the address
+
+	// Set up the socket
+	socketFD = socket(AF_INET, SOCK_STREAM, 0); // Create the socket
+	if (socketFD < 0) error("CLIENT: ERROR opening socket");
+	
+	// Connect to server
+	if (connect(socketFD, (struct sockaddr*)&serverAddress, sizeof(serverAddress)) < 0) // Connect socket to address
+		error("CLIENT: ERROR connecting");
+
+	// Get input message from user
+	printf("CLIENT: Enter text to send to the server, and then hit enter: ");
+	memset(buffer, '\0', sizeof(buffer)); // Clear out the buffer array
+	fgets(buffer, sizeof(buffer) - 1, stdin); // Get input from the user, trunc to buffer - 1 chars, leaving \0
+	buffer[strcspn(buffer, "\n")] = '\0'; // Remove the trailing \n that fgets adds
+
+	// Send message to server
+	charsWritten = send(socketFD, buffer, strlen(buffer), 0); // Write to the server
+	if (charsWritten < 0) error("CLIENT: ERROR writing to socket");
+	if (charsWritten < strlen(buffer)) printf("CLIENT: WARNING: Not all data written to socket!\n");
+
+	// Get return message from server
+	memset(buffer, '\0', sizeof(buffer)); // Clear out the buffer again for reuse
+	charsRead = recv(socketFD, buffer, sizeof(buffer) - 1, 0); // Read data from the socket, leaving \0 at end
+	if (charsRead < 0) error("CLIENT: ERROR reading from socket");
+	printf("CLIENT: I received this from the server: \"%s\"\n", buffer);
+
+	close(socketFD); // Close the socket
+	return 0;
+}

OSU Coursework/CS 344 - Operating Systems I/Assignment 4 - OTP/reference/server.c

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+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/types.h> 
+#include <sys/socket.h>
+#include <netinet/in.h>
+
+void error(const char *msg) { perror(msg); exit(1); } // Error function used for reporting issues
+
+int main(int argc, char *argv[])
+{
+	int listenSocketFD, establishedConnectionFD, portNumber, charsRead;
+	socklen_t sizeOfClientInfo;
+	char buffer[256];
+	struct sockaddr_in serverAddress, clientAddress;
+
+	if (argc < 2) { fprintf(stderr,"USAGE: %s port\n", argv[0]); exit(1); } // Check usage & args
+
+	// Set up the address struct for this process (the server)
+	memset((char *)&serverAddress, '\0', sizeof(serverAddress)); // Clear out the address struct
+	portNumber = atoi(argv[1]); // Get the port number, convert to an integer from a string
+	serverAddress.sin_family = AF_INET; // Create a network-capable socket
+	serverAddress.sin_port = htons(portNumber); // Store the port number
+	serverAddress.sin_addr.s_addr = INADDR_ANY; // Any address is allowed for connection to this process
+
+	// Set up the socket
+	listenSocketFD = socket(AF_INET, SOCK_STREAM, 0); // Create the socket
+	if (listenSocketFD < 0) error("ERROR opening socket");
+
+	// Enable the socket to begin listening
+	if (bind(listenSocketFD, (struct sockaddr *)&serverAddress, sizeof(serverAddress)) < 0) // Connect socket to port
+		error("ERROR on binding");
+	listen(listenSocketFD, 5); // Flip the socket on - it can now receive up to 5 connections
+
+	// Accept a connection, blocking if one is not available until one connects
+	sizeOfClientInfo = sizeof(clientAddress); // Get the size of the address for the client that will connect
+	establishedConnectionFD = accept(listenSocketFD, (struct sockaddr *)&clientAddress, &sizeOfClientInfo); // Accept
+	if (establishedConnectionFD < 0) error("ERROR on accept");
+
+	// Get the message from the client and display it
+	memset(buffer, '\0', 256);
+	charsRead = recv(establishedConnectionFD, buffer, 255, 0); // Read the client's message from the socket
+	if (charsRead < 0) error("ERROR reading from socket");
+	printf("SERVER: I received this from the client: \"%s\"\n", buffer);
+
+	// Send a Success message back to the client
+	charsRead = send(establishedConnectionFD, "I am the server, and I got your message", 39, 0); // Send success back
+	if (charsRead < 0) error("ERROR writing to socket");
+	close(establishedConnectionFD); // Close the existing socket which is connected to the client
+	close(listenSocketFD); // Close the listening socket
+	return 0; 
+}