Question

I have very strange problem with QProcess and it’s strange behaviour.

What i wanna get at the end is something like this (this is cmd.exe in windows 7)

C:\path_to_somewhere>cmd /c "C:\Program Files\path_to_dir\executable"

(cmd is for compatibility with show of QProcess)

So to do something like that i create this:

QProcess proc;
QString command;
QStringList attributes;

command = "c:\\windows\\system32\\cmd.exe";
QStringList << QString("/c \"C:\\Program Files\\path_to-dir\\executable"");
proc.start(command, attributes);

What i get on error output is:

Name '\"c:\Program Files\Quantum GIS Wroclaw\bin\gdalwarp.exe\"' is not recognized as
internat or external command, executable or batch file.

(it’s translated by me from polish so it may be a little diffrent in english).

Seems like the \ character is not escaped in the string, leaving the \” as to characters in command. What am I doing wrong?

I’ve tried the

proces.start(QString) 

function with triple \”\”\” and it doesnt work either. I suppose the solution of this problem has to be sooo easy that I dont event think about it.

Answer 1

As you already noted, Qt wraps arguments containing spaces with quotes, which means that the actual command issued by QProcess will look something like that (not sure about the inner quotes):

c:\windows\system32\cmd.exe "/c \"C:\Program Files\path_to_dir\executable\""

which is not what you want: the entire string is passed to cmd including /c. Since /c and the path are two arguments, you should pass them separately to QProcess, without worrying about spaces as they will be handled automatically:

QString command = "cmd.exe";
QStringList arguments = 
    QStringList() << "/c" << "C:\\Program Files\\path_to_dir\\executable";
// note there are two arguments now, and the path is not enclosed in quotes
proc.start(command, arguments);