Ripulitura dei nomi e ristrutturazione dei capitoli. Tolto simpltcp che

[gapil.git] / listati / TCP_daytime.c

diff --git a/listati/TCP_daytime.c b/listati/TCP_daytime.c
new file mode 100644 (file)
index 0000000..e1459d9
--- /dev/null
+++ b/listati/TCP_daytime.c
@@ -0,0 +1,48 @@
+#include <sys/types.h>   /* predefined types */
+#include <unistd.h>      /* include unix standard library */
+#include <arpa/inet.h>   /* IP addresses conversion utilities */
+#include <sys/socket.h>  /* socket library */
+#include <stdio.h>       /* include standard I/O library */
+
+int main(int argc, char *argv[])
+{
+    int sock_fd;
+    int i, nread;
+    struct sockaddr_in serv_add;
+    char buffer[MAXLINE];
+     ...
+    /* create socket */
+    if ( (sock_fd = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
+        perror("Socket creation error");
+        return -1;
+    }
+    /* initialize address */
+    memset((void *) &serv_add, 0, sizeof(serv_add)); /* clear server address */
+    serv_add.sin_family = AF_INET;                   /* address type is INET */
+    serv_add.sin_port = htons(13);                   /* daytime post is 13 */
+    /* build address using inet_pton */
+    if ( (inet_pton(AF_INET, argv[optind], &serv_add.sin_addr)) <= 0) {
+        perror("Address creation error");
+        return -1;
+    }
+    /* extablish connection */
+    if (connect(sock_fd, (struct sockaddr *)&serv_add, sizeof(serv_add)) < 0) {
+        perror("Connection error");
+        return -1;
+    }
+    /* read daytime from server */
+    while ( (nread = read(sock_fd, buffer, MAXLINE)) > 0) {
+        buffer[nread]=0;
+        if (fputs(buffer, stdout) == EOF) {          /* write daytime */
+            perror("fputs error");
+            return -1;
+        }
+    }
+    /* error on read */
+    if (nread < 0) {
+        perror("Read error");
+        return -1;
+    }
+    /* normal exit */
+    return 0;
+}