add concurrent, iterative and UDP servers

2 files changed, 96 insertions, 0 deletions

diff --git a/q6/a/client.c b/q6/a/client.c
new file mode 100644
index 0000000..7219476
--- /dev/null
+++ b/q6/a/client.c
@@ -0,0 +1,47 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <unistd.h>
+#include <string.h>
+#include <arpa/inet.h>
+#include <string.h>
+
+int main(int argc, char* argv[]) { 
+    const char *server_name = "127.0.0.1";
+    int sockfd, connfd; 
+    struct sockaddr_in servaddr, cli; 
+
+    sockfd = socket(AF_INET, SOCK_STREAM, 0); 
+    servaddr.sin_family = AF_INET; 
+    inet_pton(AF_INET, server_name, &servaddr.sin_addr);
+
+    int port = atoi(argv[1]);
+    servaddr.sin_port = htons(port);
+
+    if((connect(sockfd, (struct sockaddr*)&servaddr, sizeof(servaddr))) == 0) {
+        printf("Connected to server!\n");
+        fflush(stdout);
+    } else {
+        printf("Invalid or busy server address\n");
+        fflush(stdout);
+        exit(0);
+    };
+
+    int cont = 0;
+    char *buf = malloc(1024);
+    printf("Client input: ");
+    fgets(buf, 100, stdin);
+    while(strcmp(buf, "quit\n") != 0) {
+        send(sockfd, buf, 100, 0);
+        if ((cont = recv(sockfd, buf, 100, 0)) > 0) {
+            printf("Server response: %s\n", buf);;
+            fflush(stdout);
+        }
+        printf("Client input: ");
+        fgets(buf, 100, stdin);
+    };
+
+    close(sockfd); 
+}
diff --git a/q6/a/server.c b/q6/a/server.c
new file mode 100644
index 0000000..ac258c0
--- /dev/null
+++ b/q6/a/server.c
@@ -0,0 +1,49 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <unistd.h>
+#include <string.h>
+#include <arpa/inet.h>
+
+int main(int argc, char *argv[]) {
+    int sockfd, connfd; 
+    struct sockaddr_in servaddr, cli; 
+  
+    sockfd = socket(AF_INET, SOCK_STREAM, 0); 
+    servaddr.sin_family = AF_INET; 
+    servaddr.sin_addr.s_addr = htonl(INADDR_ANY); 
+
+    int port = atoi(argv[1]);
+    servaddr.sin_port = htons(port);
+  
+    bind(sockfd, (struct sockaddr *)&servaddr, sizeof(servaddr));
+  
+    listen(sockfd, 128);
+    printf("Server started at %s...\n", inet_ntoa(servaddr.sin_addr));
+    fflush(stdout);
+
+    while(1) {
+        socklen_t len = sizeof(cli);
+        connfd = accept(sockfd, (struct sockaddr *)&cli, &len);
+        int i = getpeername(connfd, (struct sockaddr*)&cli, &len);
+
+        printf("Client connected at port %d\n", htons(cli.sin_port));
+        int n;
+        char buf[100];
+
+        int pid;
+        if((pid=fork())==0){
+            close(sockfd);
+            while((n = recv(connfd, buf, 100, 0)) > 0) {
+                printf("Client message: %s\n", buf);
+                fflush(stdout);
+                send(connfd, buf, n, 0);
+            };
+            exit(0);
+        }
+        close(connfd);
+    }
+    return 0;
+}