change return type of setLinkUp/Down to int instead of bool, remove error argument

interface.cpp

@@ -44,7 +44,7 @@ m_index(-1)
 /*!
     Set the interface's administrative link state to up. Requires that the CAP_NET_ADMIN capability be set on the application binary, or run as root (\a not \a recommended). Returns 0 on success, 1 on error.
 */
-int Interface::setLinkUp(QString &error) {
+int Interface::setLinkUp() {
   struct rtnl_link *link, *link_orig = NULL;
   struct nl_sock *sock = NULL;
   QByteArray interfaceArray = m_interface.toLatin1();
@@ -75,7 +75,7 @@ int Interface::setLinkUp(QString &error) {
       rtnl_link_set_flags(link, IFF_UP);
 
       if((err = rtnl_link_change(sock, link_orig, link, 0)) < 0) {
-        error = nl_geterror(err);
+        //error = nl_geterror(err);
         rtnl_link_put(link);
         rtnl_link_put(link_orig);
         nl_socket_free(sock);
@@ -96,7 +96,7 @@ int Interface::setLinkUp(QString &error) {
 /*!
     Set the interface's administrative link state to down. Requires that the CAP_NET_ADMIN capability be set on the application binary, or run as root (\a not \a recommended). Returns 0 on success, 1 on error.
 */
-int Interface::setLinkDown(QString &error) {
+int Interface::setLinkDown() {
   struct rtnl_link *link, *link_orig = NULL;
   struct nl_sock *sock = NULL;
   QByteArray interfaceArray = m_interface.toLatin1();
@@ -127,7 +127,7 @@ int Interface::setLinkDown(QString &error) {
       rtnl_link_unset_flags(link, IFF_UP);
 
       if((err = rtnl_link_change(sock, link_orig, link, 0)) < 0) {
-        error = nl_geterror(err);
+        //error = nl_geterror(err);
         rtnl_link_put(link);
         rtnl_link_put(link_orig);
         nl_socket_free(sock);

interface.h

@@ -13,8 +13,8 @@ public:
   QStringList addresses() const;
   bool hasCarrier(bool *ok = 0);
   bool hasAdminLink(bool *ok = 0);
-  bool setLinkUp(QString &error);
-  bool setLinkDown(QString &error);
+  int setLinkUp();
+  int setLinkDown();
   int addAddress(QString address) const;
   int deleteAddress(QString address) const;
   const QString& name() const;