[Solved] ReadAll() (ls)

jocala

I need to offer a selection of mounted drives to the user for a procedure. The fragment below will show me the the contents of the directory where drive mounts live. How can I parse out the sd?? values (sda1,sdb1,etc) from the QString "command" and offer them to the user for choice?

@ QProcess mount_dir;
mount_dir.setProcessChannelMode(QProcess::MergedChannels);
cstring = adb + " -s " + daddr+port + " shell su -c ls /storage/";
mount_dir.start(cstring);
mount_dir.waitForFinished(-1);
command=mount_dir.readAll();@

Thanks!

dheerendra

Did you get the output of the ls command from QProcess in your program ? If yes, it should be simple QString parsing. QString documentation should help you.

If you have not got the output from QProcess do let me know. I can help with that.

SGaist

Hi,

Please have a look at QProcess's "extended description":http://qt-project.org/doc/qt-5/qprocess.html#details you'll see how to properly build a parameter list and start a process with it

jocala

Did you get the output of the ls command from QProcess in your program ? If >yes, it should be simple QString parsing.

Actually, parsing is what I'd like a hand with. QProcess is working great.

I have a qstring, "command" as shown in the code above. Among other things, it will contain strings of a pattern "sd??", *sda1,sdb1,sdc1, etc).

Is there a way I can grab any substring matching the pattern "sd??" from the qstring returned by readAll()?

SGaist

QRegularExpression comes to mind

jocala

Yeah, I saw that and came across this fragment in my search:

@
QRegularExpression re("(\d+) (\w+)");
QRegularExpressionMatch match = re.match("1234 word");
if (match.hasMatch()) {
QString digits = match.captured(1); // "1234"
QString letters = match.captured(2); // "word
}
@

Unfortunately, I'm not one of the 1 out of 10,000 coders who speak regex.

So, what would a regex for "sd??" be?

dheerendra

This should help you.
@
QString str = "/dev/sda1";
int index = str.indexOf("sd");
QString newStr = str.mid(index,4);
qDebug() << "Sub String ="<<newStr@

SGaist

There are several possibilities e.g.

"[a-z]{2}([a-z0-9]+)"

If you are looking for specifically sd plus something:

"sd([a-z0-9]+)"

From the top of my head.

You can build the "Regular Expressions Example" to help you build the regexp

jocala

Thanks for this. That tool is very handy.