Give gpspacket.c a real doc string.

1 files changed, 18 insertions, 2 deletions

diff --git a/gpspacket.c b/gpspacket.c
index 8dd4d857..d38ff778 100644
--- a/gpspacket.c
+++ b/gpspacket.c
@@ -70,15 +70,21 @@ Getter_init(GetterObject *self)
 static PyObject *
 Getter_get(GetterObject *self, PyObject *args)
 {
+    ssize_t len;
     int fd;
 
     if (!PyArg_ParseTuple(args, "i;missing or invalid file descriptor argument to gpspacket.get", &fd))
         return NULL;
 
-    packet_get(fd, &self->getter);
+    len = packet_get(fd, &self->getter);
     if (PyErr_Occurred())
 	return NULL;
 
+    if (len == 0) {
+	self->getter.type = BAD_PACKET;
+	self->getter.outbuffer[0] = '\0';
+    }
+
     return Py_BuildValue("(i, s)", self->getter.type, self->getter.outbuffer);
 }
 
@@ -220,7 +226,17 @@ static PyMethodDef gpspacket_methods[] = {
 };
 
 PyDoc_STRVAR(module_doc,
-"Python binding of the libgpsd module for recognizing GPS packets.");
+"Python binding of the libgpsd module for recognizing GPS packets.\n\
+The new() function returns a new packet-getter instance.  Getter instances\n\
+have two methods:\n\
+    get() takes a file descriptor argument and returns a tuple consisting of\n\
+the integer packet type and string packet value.  On end of file it returns\n\
+(-1, '').\n\
+    reset() resets the packet-getter to its initial state.\n\
+    The module also has a register_report() function that accepts a callback\n\
+for debug message reporting.  The callback will get two arguments, the error\n\
+level of the message and the message itself.\n\
+");
 
 PyMODINIT_FUNC
 initgpspacket(void)