QProcess::readAllStandardOutput() and line feeds

Question

I'm printing output from QProcess::readAllStandardOutput() (on Ubuntu 18.04) and it works otherwise fine, but \n characters are not actually line feeds and somehow appear literally as a part of the string:

/usr/local/lib/libpcl_search.so\n/usr/local/lib/libpcl_sample_consensus.so\n/usr/local/lib/libpcl_io.so\n/usr/local/lib/libpcl_segmentation.so\n/usr/local/lib/libpcl_common.so\n/usr/local/lib/libboost_random.so\n/usr/local/lib/libboost_math_tr1l.so

That was output when running find / -name "*so" command with QProcess printed like this:

qDebug() << m_process->readAllStandardOutput();

I guess this is an encoding issue..?

Answer 1

the problem is caused because QDebug is going to show the endlines and similar characters because you are passing them a QByteArray, if you want to see the output you want then use qPrintable:

#include <QCoreApplication>
#include <QProcess>
#include <QDebug>

int main(int argc, char *argv[])
{
    QCoreApplication a(argc, argv);

    QProcess process;

    QObject::connect(&process, &QProcess::readyReadStandardOutput, [&process](){
        qDebug()<< qPrintable(process.readAllStandardOutput());
    });
    process.start("find / -name \"*so\"");

    return a.exec();
}

Output:

/snap/core/4917/lib/crda/libreg.so
/snap/core/4917/lib/i386-linux-gnu/ld-2.23.so
/snap/core/4917/lib/i386-linux-gnu/libBrokenLocale-2.23.so
/snap/core/4917/lib/i386-linux-gnu/libSegFault.so
/snap/core/4917/lib/i386-linux-gnu/libanl-2.23.so
/snap/core/4917/lib/i386-linux-gnu/libc-2.23.so
/snap/core/4917/lib/i386-linux-gnu/libcidn-2.23.so
...