--- libftdi-0.20/src/ftdi.c	2012-11-16 10:32:50.000000000 -0600
+++ ftdi.eperm.c	2012-11-16 10:30:12.303281040 -0600
@@ -358,6 +358,8 @@
 int ftdi_usb_get_strings(struct ftdi_context * ftdi, struct usb_device * dev,
                          char * manufacturer, int mnf_len, char * description, int desc_len, char * serial, int serial_len)
 {
+    int err;
+
     if ((ftdi==NULL) || (dev==NULL))
         return -1;
 
@@ -366,27 +368,33 @@
 
     if (manufacturer != NULL)
     {
-        if (usb_get_string_simple(ftdi->usb_dev, dev->descriptor.iManufacturer, manufacturer, mnf_len) <= 0)
+        if ((err = usb_get_string_simple(ftdi->usb_dev, dev->descriptor.iManufacturer, manufacturer, mnf_len)) <= 0)
         {
             ftdi_usb_close_internal (ftdi);
+            if (err == -EPERM)
+              ftdi_error_return(-4, usb_strerror());
             ftdi_error_return(-7, usb_strerror());
         }
     }
 
     if (description != NULL)
     {
-        if (usb_get_string_simple(ftdi->usb_dev, dev->descriptor.iProduct, description, desc_len) <= 0)
+        if ((err = usb_get_string_simple(ftdi->usb_dev, dev->descriptor.iProduct, description, desc_len)) <= 0)
         {
             ftdi_usb_close_internal (ftdi);
+            if (err == -EPERM)
+              ftdi_error_return(-4, usb_strerror());
             ftdi_error_return(-8, usb_strerror());
         }
     }
 
     if (serial != NULL)
     {
-        if (usb_get_string_simple(ftdi->usb_dev, dev->descriptor.iSerialNumber, serial, serial_len) <= 0)
+        if ((err = usb_get_string_simple(ftdi->usb_dev, dev->descriptor.iSerialNumber, serial, serial_len)) <= 0)
         {
             ftdi_usb_close_internal (ftdi);
+            if (err == -EPERM)
+              ftdi_error_return(-4, usb_strerror());
             ftdi_error_return(-9, usb_strerror());
         }
     }
@@ -641,6 +649,7 @@
     struct usb_bus *bus;
     struct usb_device *dev;
     char string[256];
+    int err;
 
     usb_init();
 
@@ -664,9 +673,11 @@
 
                 if (description != NULL)
                 {
-                    if (usb_get_string_simple(ftdi->usb_dev, dev->descriptor.iProduct, string, sizeof(string)) <= 0)
+                    if ((err = usb_get_string_simple(ftdi->usb_dev, dev->descriptor.iProduct, string, sizeof(string))) <= 0)
                     {
                         ftdi_usb_close_internal (ftdi);
+                        if (err == -EPERM)
+                          ftdi_error_return(-4, "unable to fetch product description");
                         ftdi_error_return(-8, "unable to fetch product description");
                     }
                     if (strncmp(string, description, sizeof(string)) != 0)
@@ -678,9 +689,11 @@
                 }
                 if (serial != NULL)
                 {
-                    if (usb_get_string_simple(ftdi->usb_dev, dev->descriptor.iSerialNumber, string, sizeof(string)) <= 0)
+                    if ((err = usb_get_string_simple(ftdi->usb_dev, dev->descriptor.iSerialNumber, string, sizeof(string))) <= 0)
                     {
                         ftdi_usb_close_internal (ftdi);
+                        if (err == -EPERM)
+                          ftdi_error_return(-4, "unable to fetch serial number");
                         ftdi_error_return(-9, "unable to fetch serial number");
                     }
                     if (strncmp(string, serial, sizeof(string)) != 0)