Qt for HarmonyOS/qtohosextras doc/Want FDs Sender Example

Want FDs Sender Example

Demonstrates sending open file descriptors to another ability through a want.

The form collects the target bundle, module and ability names and a set of files chosen through a file dialog. Send FD opens every file, stores its handle in QOhosWant::fds under the keys keyFd0, keyFd1 and so on, logs the dev / ino numbers for cross-checking on the receiver side, and starts the target with QtOhosExtras::startAbility().

The want is filled with the target names:

     QtOhosExtras::QOhosWant want;
     want.bundleName = bundleName;
     want.moduleName = m_moduleNameEdit->text().trimmed();
     want.abilityName = abilityName;

Each open file descriptor is stored under its own key:

         const QString fdKey = QStringLiteral("keyFd%1").arg(openedCount);
         want.fds.insert(fdKey, fd);

Finally the target ability is started with the want:

     const auto operationStatus = QtOhosExtras::startAbility(want);
     appendLog(QStringLiteral("startAbility: success=%1").arg(!operationStatus.isNull() && operationStatus->success()));

Note: The descriptors must still be open when startAbility() is called, so the QFile objects are kept alive for the duration of the call. Use application-specific keys and do not reuse a key in both QOhosWant::fds and QOhosWant::parameters.

Files:

• abilitycontext/wantfdssender/main.cpp
• abilitycontext/wantfdssender/wantfdssender.pro