fixed send(from) recv(from) bug, added dgramrcv.c

[my-code/ivac.git] / dgramrcv.c

diff --git a/dgramrcv.c b/dgramrcv.c
new file mode 100644 (file)
index 0000000..060fd4a
--- /dev/null
+++ b/dgramrcv.c
@@ -0,0 +1,66 @@
+/* dgramrcv.c - receive from udp server
+ *
+ * author: hackbard
+ *
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+/* memset */
+#include <string.h>
+
+/* socket and bind stuff */
+#include <sys/types.h>
+#include <sys/socket.h>
+
+/* sockkaddr_in */
+#include <netinet/in.h>
+
+/* inet_ntoa ... */
+#include <arpa/inet.h>
+
+/* errno stuff ... */
+#include <errno.h>
+
+/* read, close */
+#include <unistd.h>
+
+int main(int argc, char *argv[]) {
+  int receive_fd;
+  struct sockaddr_in target_addr;
+  int receive_bytes, write_bytes;
+  socklen_t target_addr_len,optlen;
+
+  if(argc!=3) {
+    printf("usage: %s <target-ip> <port>\n",argv[0]);
+    exit(1);
+  }
+
+  if((receive_fd=socket(AF_INET,SOCK_DGRAM,0)) == -1) {
+    printf("can't open socket.\n");
+    exit(1);
+  }
+
+  optlen=1;
+  setsockopt(receive_fd,SOL_SOCKET,SO_BROADCAST,NULL,optlen);
+ 
+  memset(&target_addr,0,sizeof(target_addr));
+  target_addr.sin_family=AF_INET;
+  target_addr.sin_port=htons(atoi(argv[2]));
+  target_addr.sin_addr.s_addr=inet_addr(argv[1]);
+  target_addr_len=sizeof(target_addr);
+
+  receive_bytes=1;
+  while(receive_bytes>0) {
+       unsigned char buf[1000];
+       receive_bytes=recvfrom(receive_fd,buf,sizeof(buf),0,(struct sockaddr *)&target_addr,&target_addr_len);
+        write_bytes=write(1,buf,receive_bytes);
+  }
+
+  close(receive_fd);
+  printf("connection closed ...\n");
+  printf("%d from %d total bytes written.\n",write_bytes,receive_bytes);
+  
+  return 0;
+}