qt-everywhere-src-5.14.1/qtbase/src/corelib/doc/snippets/code/src_corelib_io_qprocess.cpp

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void wrapInFunction()
{

//! [0]
QProcess builder;
builder.setProcessChannelMode(QProcess::MergedChannels);
builder.start("make", QStringList() << "-j2");

if (!builder.waitForFinished())
    qDebug() << "Make failed:" << builder.errorString();
else
    qDebug() << "Make output:" << builder.readAll();
//! [0]


//! [1]
QProcess more;
more.start("more");
more.write("Text to display");
more.closeWriteChannel();
// QProcess will emit readyRead() once "more" starts printing
//! [1]


//! [2]
command1 | command2
//! [2]


//! [3]
QProcess process1;
QProcess process2;

process1.setStandardOutputProcess(&process2);

process1.start("command1");
process2.start("command2");
//! [3]


//! [4]
class SandboxProcess : public QProcess
{
    ...
 protected:
     void setupChildProcess() override;
    ...
};

void SandboxProcess::setupChildProcess()
{
    // Drop all privileges in the child process, and enter
    // a chroot jail.
#if defined Q_OS_UNIX
    ::setgroups(0, 0);
    ::chroot("/etc/safe");
    ::chdir("/");
    ::setgid(safeGid);
    ::setuid(safeUid);
    ::umask(0);
#endif
}

//! [4]


//! [5]
QProcess process;
process.start("del /s *.txt");
// same as process.start("del", QStringList() << "/s" << "*.txt");
...
//! [5]


//! [6]
QProcess process;
process.start("dir \"My Documents\"");
//! [6]


//! [7]
QProcess process;
process.start("dir \"Epic 12\"\"\" Singles\"");
//! [7]


//! [8]
QStringList environment = QProcess::systemEnvironment();
// environment = {"PATH=/usr/bin:/usr/local/bin",
//                "USER=greg", "HOME=/home/greg"}
//! [8]

}