diff --git a/libguac/src/client.c b/libguac/src/client.c
index 3de42f73..276c7f83 100644
--- a/libguac/src/client.c
+++ b/libguac/src/client.c
@@ -190,9 +190,14 @@ guac_client* guac_get_client(int client_fd) {
                     return NULL;
                 }
 
-                /* Send args */
-                guac_send_args(io, client_args);
-                guac_flush(io);
+                if (   /* Send args */
+                       guac_send_args(io, client_args)
+                    || guac_flush(io)
+                   ) {
+                    guac_close(io);
+                    guac_free_instruction_data(&instruction);
+                    return NULL;
+                }
 
                 guac_free_instruction_data(&instruction);
                 break;
@@ -292,8 +297,13 @@ void* __guac_client_output_thread(void* data) {
         long timestamp = guac_current_timestamp();
         if (timestamp - client->last_sent_timestamp > GUAC_SYNC_FREQUENCY) {
             client->last_sent_timestamp = timestamp;
-            guac_send_sync(io, timestamp);
-            guac_flush(io);
+            if (
+                   guac_send_sync(io, timestamp)
+                || guac_flush(io)
+               ) {
+                guac_client_stop(client);
+                return NULL;
+            }
         }
 
         /* Handle server messages */
@@ -320,11 +330,18 @@ void* __guac_client_output_thread(void* data) {
 
                     /* Send sync instruction */
                     client->last_sent_timestamp = guac_current_timestamp();
-                    guac_send_sync(io, client->last_sent_timestamp);
+                    if (guac_send_sync(io, client->last_sent_timestamp)) {
+                        guac_client_stop(client);
+                        return NULL;
+                    }
 
                 }
 
-                guac_flush(io);
+                if (guac_flush(io)) {
+                    guac_client_stop(client);
+                    return NULL;
+                }
+
             }
 
             /* If sync threshold exceeded, don't spin waiting for resync */
diff --git a/libguac/src/protocol.c b/libguac/src/protocol.c
index 2591edd3..db003763 100644
--- a/libguac/src/protocol.c
+++ b/libguac/src/protocol.c
@@ -214,7 +214,7 @@ int guac_send_name(GUACIO* io, const char* name) {
 int guac_send_size(GUACIO* io, int w, int h) {
 
     return
-        guac_write_string(io, "size:")
+           guac_write_string(io, "size:")
         || guac_write_int(io, w)
         || guac_write_string(io, ",")
         || guac_write_int(io, h)
@@ -227,7 +227,7 @@ int guac_send_clipboard(GUACIO* io, const char* data) {
     char* escaped = guac_escape_string(data); 
 
     if (
-        guac_write_string(io, "clipboard:")
+           guac_write_string(io, "clipboard:")
         || guac_write_string(io, escaped)
         || guac_write_string(io, ";")
        ) {
@@ -245,7 +245,7 @@ int guac_send_error(GUACIO* io, const char* error) {
     char* escaped = guac_escape_string(error); 
 
     if (
-        guac_write_string(io, "error:")
+           guac_write_string(io, "error:")
         || guac_write_string(io, escaped)
         || guac_write_string(io, ";")
        ) {
@@ -261,7 +261,7 @@ int guac_send_error(GUACIO* io, const char* error) {
 int guac_send_sync(GUACIO* io, long timestamp) {
 
     return 
-        guac_write_string(io, "sync:")
+           guac_write_string(io, "sync:")
         || guac_write_int(io, timestamp)
         || guac_write_string(io, ";");
 
@@ -270,7 +270,7 @@ int guac_send_sync(GUACIO* io, long timestamp) {
 int guac_send_copy(GUACIO* io, int srcl, int srcx, int srcy, int w, int h, int dstl, int dstx, int dsty) {
 
     return
-        guac_write_string(io, "copy:")
+           guac_write_string(io, "copy:")
         || guac_write_int(io, srcl)
         || guac_write_string(io, ",")
         || guac_write_int(io, srcx)
@@ -419,7 +419,7 @@ int guac_send_cursor(GUACIO* io, int x, int y, png_byte** png_rows, int w, int h
     );
     
     if (
-        guac_write_string(io, "cursor:")
+           guac_write_string(io, "cursor:")
         || guac_write_int(io, x)
         || guac_write_string(io, ",")
         || guac_write_int(io, y)