QHostAddress error in convert to string?

[brunjak]

Hi,
I'm confused about QHostAddress class. The following example results in the following output:

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

const QString hostAddress_string1 = "192.168.0.20";
const QString hostAddress_string2 = "192.168.000.020";
QHostAddress hostAddress1;
QHostAddress hostAddress2;

hostAddress1.setAddress(hostAddress_string1);
hostAddress2.setAddress(hostAddress_string2);

const QString hostAddress_string12 = hostAddress1.toString();
const QString hostAddress_string22 = hostAddress2.toString();

qDebug() << "String  1 " << hostAddress_string1;
qDebug() << "String 12 " << hostAddress_string12;

qDebug() << "String  2 " << hostAddress_string2;
qDebug() << "String 22 " << hostAddress_string22;

return a.exec();

}

Output:
String 1 "192.168.0.20"
String 12 "192.168.0.20"
String 2 "192.168.000.020"
String 22 "192.168.0.16"

I'm using QT 5.5.0. Is this a bug?

Thank you
Jakob

[Joel Bodenmann]

That's not a bug. The function apparently converts the string into a literal value (a number). In C/C++ a leading zero indicates an octal value. And 20 octal happens to be 16 in decimal.
You might want to manually convert the string into a number and then pass that number to QHostAddress::setAddress() to avoid this problem. After all QHostAddress::setAddress() does its job correctly and the return value will be true.

Specification:

The string may begin with an arbitrary amount of white space (as determined by isspace(3)) followed by a single optional '+' or '-' sign. If base is zero or 16, the string may then include a "0x" prefix, and the number will be read in base 16; otherwise, a zero base is taken as 10 (decimal) unless the next character is '0', in which case it is taken as 8 (octal).

[brunjak]

... thank you.