Improve based on feedback

Author: andy1li

compiled_starters/cpp/src/main.cpp

@@ -3,57 +3,56 @@
 #include <iostream>
 #include <netdb.h>
 #include <string>
-#include <system_error>
 #include <unistd.h>
 #include <arpa/inet.h>
 #include <sys/socket.h>
 #include <sys/types.h>
 
 int main(int argc, char* argv[]) {
-    // Flush after every std::cout / std::cerr
+    // Disable output buffering
     std::cout << std::unitbuf;
     std::cerr << std::unitbuf;
 
-    // You can use print statements as follows for debugging, they'll be visible when running tests.
-    std::cerr << "Logs from your program will appear here!\n";
-
-    // Create socket
     int server_fd = socket(AF_INET, SOCK_STREAM, 0);
     if (server_fd < 0) {
-        throw std::system_error(errno, std::generic_category(), "Failed to create server socket");
+        std::cerr << "Failed to create server socket: " << std::endl;
+        return 1;
     }
 
-    // Set socket options
+    // Since the tester restarts your program quite often, setting SO_REUSEADDR
+    // ensures that we don't run into 'Address already in use' errors
     int reuse = 1;
     if (setsockopt(server_fd, SOL_SOCKET, SO_REUSEADDR, &reuse, sizeof(reuse)) < 0) {
         close(server_fd);
-        throw std::system_error(errno, std::generic_category(), "setsockopt failed");
+        std::cerr << "setsockopt failed: " << std::endl;
+        return 1;
     }
 
-    // Configure server address
     struct sockaddr_in server_addr{};
     server_addr.sin_family = AF_INET;
     server_addr.sin_addr.s_addr = INADDR_ANY;
     server_addr.sin_port = htons(9092);
 
-    // Bind socket
     if (bind(server_fd, reinterpret_cast<struct sockaddr*>(&server_addr), sizeof(server_addr)) != 0) {
         close(server_fd);
-        throw std::system_error(errno, std::generic_category(), "Failed to bind to port 9092");
+        std::cerr << "Failed to bind to port 9092" << std::endl;
+        return 1;
     }
 
-    // Listen for connections
     int connection_backlog = 5;
     if (listen(server_fd, connection_backlog) != 0) {
         close(server_fd);
-        throw std::system_error(errno, std::generic_category(), "listen failed");
+        std::cerr << "listen failed" << std::endl;
+        return 1;
     }
 
     std::cout << "Waiting for a client to connect...\n";
 
-    // Accept client connection
     struct sockaddr_in client_addr{};
     socklen_t client_addr_len = sizeof(client_addr);
+
+    // You can use print statements as follows for debugging, they'll be visible when running tests.
+    std::cerr << "Logs from your program will appear here!\n";
 
     // Uncomment this block to pass the first stage
     // 

course-definition.yml

@@ -16,7 +16,6 @@ completion_percentage: 15
 
 languages:
   - slug: "cpp"
-    release_status: "alpha"
   - slug: "gleam"
   - slug: "go"
   - slug: "java"

solutions/cpp/01-vi6/code/src/main.cpp

@@ -3,55 +3,54 @@
 #include <iostream>
 #include <netdb.h>
 #include <string>
-#include <system_error>
 #include <unistd.h>
 #include <arpa/inet.h>
 #include <sys/socket.h>
 #include <sys/types.h>
 
 int main(int argc, char* argv[]) {
-    // Flush after every std::cout / std::cerr
+    // Disable output buffering
     std::cout << std::unitbuf;
     std::cerr << std::unitbuf;
 
-    // Create socket
     int server_fd = socket(AF_INET, SOCK_STREAM, 0);
     if (server_fd < 0) {
-        throw std::system_error(errno, std::generic_category(), "Failed to create server socket");
+        std::cerr << "Failed to create server socket: " << std::endl;
+        return 1;
     }
 
-    // Set socket options
+    // Since the tester restarts your program quite often, setting SO_REUSEADDR
+    // ensures that we don't run into 'Address already in use' errors
     int reuse = 1;
     if (setsockopt(server_fd, SOL_SOCKET, SO_REUSEADDR, &reuse, sizeof(reuse)) < 0) {
         close(server_fd);
-        throw std::system_error(errno, std::generic_category(), "setsockopt failed");
+        std::cerr << "setsockopt failed: " << std::endl;
+        return 1;
     }
 
-    // Configure server address
     struct sockaddr_in server_addr{};
     server_addr.sin_family = AF_INET;
     server_addr.sin_addr.s_addr = INADDR_ANY;
     server_addr.sin_port = htons(9092);
 
-    // Bind socket
     if (bind(server_fd, reinterpret_cast<struct sockaddr*>(&server_addr), sizeof(server_addr)) != 0) {
         close(server_fd);
-        throw std::system_error(errno, std::generic_category(), "Failed to bind to port 9092");
+        std::cerr << "Failed to bind to port 9092" << std::endl;
+        return 1;
     }
 
-    // Listen for connections
     int connection_backlog = 5;
     if (listen(server_fd, connection_backlog) != 0) {
         close(server_fd);
-        throw std::system_error(errno, std::generic_category(), "listen failed");
+        std::cerr << "listen failed" << std::endl;
+        return 1;
     }
 
     std::cout << "Waiting for a client to connect...\n";
 
-    // Accept client connection
     struct sockaddr_in client_addr{};
     socklen_t client_addr_len = sizeof(client_addr);
-    
+
     int client_fd = accept(server_fd, reinterpret_cast<struct sockaddr*>(&client_addr), &client_addr_len);
     std::cout << "Client connected\n";
     close(client_fd);

solutions/cpp/01-vi6/diff/src/main.cpp.diff

@@ -1,61 +1,32 @@
-@@ -1,66 +1,61 @@
- #include <cstdlib>
- #include <cstring>
- #include <iostream>
- #include <netdb.h>
- #include <string>
- #include <system_error>
- #include <unistd.h>
- #include <arpa/inet.h>
- #include <sys/socket.h>
- #include <sys/types.h>
-
- int main(int argc, char* argv[]) {
-     // Flush after every std::cout / std::cerr
-     std::cout << std::unitbuf;
-     std::cerr << std::unitbuf;
-
--    // You can use print statements as follows for debugging, they'll be visible when running tests.
--    std::cerr << "Logs from your program will appear here!\n";
--
-     // Create socket
-     int server_fd = socket(AF_INET, SOCK_STREAM, 0);
-     if (server_fd < 0) {
-         throw std::system_error(errno, std::generic_category(), "Failed to create server socket");
-     }
-
-     // Set socket options
-     int reuse = 1;
-     if (setsockopt(server_fd, SOL_SOCKET, SO_REUSEADDR, &reuse, sizeof(reuse)) < 0) {
-         close(server_fd);
-         throw std::system_error(errno, std::generic_category(), "setsockopt failed");
+@@ -29,37 +29,32 @@
      }
 
-     // Configure server address
      struct sockaddr_in server_addr{};
      server_addr.sin_family = AF_INET;
      server_addr.sin_addr.s_addr = INADDR_ANY;
      server_addr.sin_port = htons(9092);
 
-     // Bind socket
      if (bind(server_fd, reinterpret_cast<struct sockaddr*>(&server_addr), sizeof(server_addr)) != 0) {
          close(server_fd);
-         throw std::system_error(errno, std::generic_category(), "Failed to bind to port 9092");
+         std::cerr << "Failed to bind to port 9092" << std::endl;
+         return 1;
      }
 
-     // Listen for connections
      int connection_backlog = 5;
      if (listen(server_fd, connection_backlog) != 0) {
          close(server_fd);
-         throw std::system_error(errno, std::generic_category(), "listen failed");
+         std::cerr << "listen failed" << std::endl;
+         return 1;
      }
 
      std::cout << "Waiting for a client to connect...\n";
 
-     // Accept client connection
      struct sockaddr_in client_addr{};
      socklen_t client_addr_len = sizeof(client_addr);
-     
+
+-    // You can use print statements as follows for debugging, they'll be visible when running tests.
+-    std::cerr << "Logs from your program will appear here!\n";
+-    
 -    // Uncomment this block to pass the first stage
 -    // 
 -    // int client_fd = accept(server_fd, reinterpret_cast<struct sockaddr*>(&client_addr), &client_addr_len);

starter_templates/cpp/code/src/main.cpp

@@ -3,57 +3,56 @@
 #include <iostream>
 #include <netdb.h>
 #include <string>
-#include <system_error>
 #include <unistd.h>
 #include <arpa/inet.h>
 #include <sys/socket.h>
 #include <sys/types.h>
 
 int main(int argc, char* argv[]) {
-    // Flush after every std::cout / std::cerr
+    // Disable output buffering
     std::cout << std::unitbuf;
     std::cerr << std::unitbuf;
 
-    // You can use print statements as follows for debugging, they'll be visible when running tests.
-    std::cerr << "Logs from your program will appear here!\n";
-
-    // Create socket
     int server_fd = socket(AF_INET, SOCK_STREAM, 0);
     if (server_fd < 0) {
-        throw std::system_error(errno, std::generic_category(), "Failed to create server socket");
+        std::cerr << "Failed to create server socket: " << std::endl;
+        return 1;
     }
 
-    // Set socket options
+    // Since the tester restarts your program quite often, setting SO_REUSEADDR
+    // ensures that we don't run into 'Address already in use' errors
     int reuse = 1;
     if (setsockopt(server_fd, SOL_SOCKET, SO_REUSEADDR, &reuse, sizeof(reuse)) < 0) {
         close(server_fd);
-        throw std::system_error(errno, std::generic_category(), "setsockopt failed");
+        std::cerr << "setsockopt failed: " << std::endl;
+        return 1;
     }
 
-    // Configure server address
     struct sockaddr_in server_addr{};
     server_addr.sin_family = AF_INET;
     server_addr.sin_addr.s_addr = INADDR_ANY;
     server_addr.sin_port = htons(9092);
 
-    // Bind socket
     if (bind(server_fd, reinterpret_cast<struct sockaddr*>(&server_addr), sizeof(server_addr)) != 0) {
         close(server_fd);
-        throw std::system_error(errno, std::generic_category(), "Failed to bind to port 9092");
+        std::cerr << "Failed to bind to port 9092" << std::endl;
+        return 1;
     }
 
-    // Listen for connections
     int connection_backlog = 5;
     if (listen(server_fd, connection_backlog) != 0) {
         close(server_fd);
-        throw std::system_error(errno, std::generic_category(), "listen failed");
+        std::cerr << "listen failed" << std::endl;
+        return 1;
     }
 
     std::cout << "Waiting for a client to connect...\n";
 
-    // Accept client connection
     struct sockaddr_in client_addr{};
     socklen_t client_addr_len = sizeof(client_addr);
+
+    // You can use print statements as follows for debugging, they'll be visible when running tests.
+    std::cerr << "Logs from your program will appear here!\n";
 
     // Uncomment this block to pass the first stage
     //