diff --git a/libguac/include/guacio.h b/libguac/include/guacio.h
index f0ee209d..9271c792 100644
--- a/libguac/include/guacio.h
+++ b/libguac/include/guacio.h
@@ -125,9 +125,13 @@ typedef struct GUACIO {
  * Allocates and initializes a new GUACIO object with the given open
  * file descriptor.
  *
+ * If an error occurs while allocating the GUACIO object, NULL is returned,
+ * and guac_error is set appropriately.
+ *
  * @param fd An open file descriptor that this GUACIO object should manage.
  * @return A newly allocated GUACIO object associated with the given
- *         file descriptor.
+ *         file descriptor, or NULL if an error occurs while allocating
+ *         the GUACIO object.
  */
 GUACIO* guac_open(int fd);
 
@@ -147,6 +151,9 @@ int64_t guac_parse_int(const char* str);
  * written may be buffered until the buffer is flushed automatically or
  * manually.
  *
+ * If an error occurs while writing, a non-zero value is returned, and
+ * guac_error is set appropriately.
+ *
  * @param io The GUACIO object to write to.
  * @param i The unsigned int to write.
  * @return Zero on success, or non-zero if an error occurs while writing.
@@ -160,6 +167,9 @@ ssize_t guac_write_int(GUACIO* io, int64_t i);
  * internally by the Guacamole protocol (commas, semicolons, or
  * backslashes) it will need to be escaped.
  *
+ * If an error occurs while writing, a non-zero value is returned, and
+ * guac_error is set appropriately.
+ *
  * @param io The GUACIO object to write to.
  * @param str The string to write.
  * @return Zero on success, or non-zero if an error occurs while writing.
@@ -174,6 +184,9 @@ ssize_t guac_write_string(GUACIO* io, const char* str);
  * be made before non-base64 writes (or writes of an independent block of
  * base64 data) can be made.
  *
+ * If an error occurs while writing, a non-zero value is returned, and
+ * guac_error is set appropriately.
+ *
  * @param io The GUACIO object to write to.
  * @param buf A buffer containing the data to write.
  * @param count The number of bytes to write.
@@ -184,6 +197,9 @@ ssize_t guac_write_base64(GUACIO* io, const void* buf, size_t count);
 /**
  * Flushes the base64 buffer, writing padding characters as necessary.
  *
+ * If an error occurs while writing, a non-zero value is returned, and
+ * guac_error is set appropriately.
+ *
  * @param io The GUACIO object to flush
  * @return Zero on success, or non-zero if an error occurs during flush.
  */
@@ -192,6 +208,9 @@ ssize_t guac_flush_base64(GUACIO* io);
 /**
  * Flushes the write buffer.
  *
+ * If an error occurs while writing, a non-zero value is returned, and
+ * guac_error is set appropriately.
+ *
  * @param io The GUACIO object to flush
  * @return Zero on success, or non-zero if an error occurs during flush.
  */
diff --git a/libguac/src/guacio.c b/libguac/src/guacio.c
index 4d2979da..b59a157c 100644
--- a/libguac/src/guacio.c
+++ b/libguac/src/guacio.c
@@ -53,6 +53,7 @@
 #include <sys/time.h>
 
 #include "guacio.h"
+#include "error.h"
 
 char __GUACIO_BASE64_CHARACTERS[64] = {
     'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P',
@@ -64,6 +65,13 @@ char __GUACIO_BASE64_CHARACTERS[64] = {
 GUACIO* guac_open(int fd) {
 
     GUACIO* io = malloc(sizeof(GUACIO));
+
+    /* If no memory available, return with error */
+    if (io == NULL) {
+        guac_error = GUAC_STATUS_NO_MEMORY;
+        return NULL;
+    }
+
     io->ready = 0;
     io->written = 0;
     io->total_written = 0;
@@ -72,6 +80,15 @@ GUACIO* guac_open(int fd) {
     /* Allocate instruction buffer */
     io->instructionbuf_size = 1024;
     io->instructionbuf = malloc(io->instructionbuf_size);
+
+    /* If no memory available, return with error */
+    if (io->instructionbuf == NULL) {
+        guac_error = GUAC_STATUS_NO_MEMORY;
+        free(io);
+        return NULL;
+    }
+
+    /* Init members */
     io->instructionbuf_used_length = 0;
     io->instructionbuf_parse_start = 0;
     io->instructionbuf_elementc = 0;
@@ -99,6 +116,10 @@ ssize_t __guac_write(GUACIO* io, const char* buf, int count) {
     retval = write(io->fd, buf, count);
 #endif
 
+    /* Record errors in guac_error */
+    if (retval < 0)
+        guac_error = GUAC_STATUS_OUTPUT_ERROR;
+
     return retval;
 }