QProcess probably reads command incorrectly

[Sucharek]

Hi, I'm having problems with using QProcess. I'm trying to send a command with special characters, so I modified the command so I'm able to put it in QProcess. When I run the command in cmd, it works. I verified the command is the same by taking the command from QProcess and putting it into a file. I ran the command that was put in the file and it worked. So I'm 100% sure the commands are the same, but QProcess for some reason doesn't want to work with it.

Here's what I'm doing (this is running in a foreach loop):

entry.replace(" ", "\\ ");
QString command = "[ -e \"/sdcard/" + entry + "\" ] && echo yes || echo no";
qDebug() << "command running for:" << entry; //entry is "File woth... spaces.txt"
qDebug() << "current command:" << command;

QProcess check;
check.start("adb", QStringList() << "-s" << dev << "shell" << command);
check.waitForFinished(INT_MAX);
qDebug() << "result:" << check.readAll(); //prints "no", should print "yes"

To put the current command in a file to test it's the same, here's what I did:

QFile a("C:/Users/.../Desktop/out.txt");
a.open(QIODevice::ReadWrite);
a.resize(0);
QStringList verify;
a.write("qprocess command: adb " + verify.join(" ").toUtf8());
a.close();

If I run the command in that file, cmd prints yes.

How can I fix this?

[JonB]

@Sucharek
You have a command line, with symbols like && and ||. Only the shell/command interpreter can handle those. That means the command to run must be Windows cmd. You would have to try something like

check.start("cmd", QStringList() << "/c" << "adb -e \"...\" ... && echo yes || echo no");

If you don't need the && ... stuff, you might be able to invoke adb directly with something like

check.start("adb", QStringList() << "-e" << "/sdcard/" + entry << ...;

Note in the latter case you (probably) do not put embedded \"s in the string.

[Sucharek]

Hi @JonB, the && and || are part of the adb shell command.
I tried using cmd /C adb... instead of just adb..., but it doesn't work.

Removing \" actually worked! Thanks!

[JonB]

@Sucharek said in QProcess probably reads command incorrectly:

Hi @JonB, the && and || are part of the adb shell command.

Ah, I thought they were cmd shell commands (like in Linux)!

Then yes to removing the quotes. If your command like is like

adb ... "def ghi" ...

then the shell/cmd where you type deals with those quotes to make a single argument. For QProcess you pass the desired string as a single argument but without any embedded quotes, like:

QStringList() << ... << "abc def" << ...;

[Kent-Dorfman]

@JonB said in QProcess probably reads command incorrectly:

Ah, I thought they were cmd shell commands (like in Linux)!

Actually they still are. The adb shell command opens a remote bash shell on an android device.

[JonB]

@Kent-Dorfman
LOL :)

BTW, I developed products using adb in the late 80s under UNIX before gdb was available. It was "painful"/"interesting" :)