Make it easier to tell if a zero read/write happened or an error

1 files changed, 4 insertions, 1 deletions

diff --git a/libvxi11client/libvxi11client.c b/libvxi11client/libvxi11client.c
index 586e84f..601e490 100644
--- a/libvxi11client/libvxi11client.c
+++ b/libvxi11client/libvxi11client.c
@@ -200,8 +200,10 @@ int vxi11_write(VXI11Context* context, char* data, int len, bool waitlock, bool
 	params.data.data_val = data;
 
 	Device_WriteResp* resp = device_write_1(&params, context->clnt);
-	if (resp != NULL && resp->error == 0)
+	if (resp != NULL && resp->error == 0) {
+		errno = 0;
 		return resp->size;
+	}
 	else if (resp == NULL ) {
 		errno = ERRNO_NULLRESULT;
 		return 0;
@@ -230,6 +232,7 @@ int vxi11_read(VXI11Context* context, char* buffer, unsigned int bufferlen, bool
 #ifdef DEBUG
 		printf("Got \"%s\" from server\n", resp->data.data_val);
 #endif
+		errno = 0;
 		if (buffer != NULL && resp->data.data_val != NULL ) {
 			int lengthtocopy = ((bufferlen - 1) < resp->data.data_len ? (bufferlen - 1) : resp->data.data_len);
 			strncpy(buffer, resp->data.data_val, lengthtocopy);