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file log output script execution windows not created on Windows

  • I've passed really 2 days to search and test but nothing works. I'm really disepointed.

    In fact, from my Qt5 application, I'm executing an Oracle SQL script and I want to trace output results to a log file to know if there's any error. I'm exectuting the following command using QProcess.

    sqlplus myUser/user_pwd@orcl @"path_to_script\script_ora.sql" >"path_to_log\\exec_script.log"

    but the log file is not created and I really don't why. I've used static log path, I've tried to change "\" by "/" but nothing works. I've verified that I can write into the ouput path and I run the MSVS as an admin

    Can anyone tell what I'm missing or what's wrong ?

    Many thanks in advance.

  • @mourad_bilog
    You cannot do redirection --- > --- in an OS command, nothing to do with Qt. You have two approaches.

    Use cmd /c, the "shell", to do it (be careful about quoting & backslashes):

    QProcess p;
    p.start('cmd', QStringList() << "/c" << "sqlplus \"myUser/user_pwd@orcl\" \"@path_to_script\\script_ora.sql\" >\"path_to_log\\exec_script.log\"");

    or do the redirection form Qt, something like:

    QProcess p;
    p.start('sqlplus', QStringList() << "myUser/user_pwd@orcl" << "@path_to_script\\script_ora.sql");

    You will have to check the quote/backslash embedding, but these are the two ways of going about it to handle redirection.

  • @JonB Many thanks for your helpful reply.

    But with the code below

    m_sCommandQuery = QString("sqlplus %1/%2@%3 @\"%4\\%5\" > %4\\exe_scrip.log ").arg(m_sDbUser, m_sDbPwd, m_sDbName, script_path.replace("/","\\"), script_name);
    		argList << "/c" << m_sCommandQuery;
    		process->start("cmd", argList);

    I've the following error

    Process finished ==> Error :  'sqlplus' n'est pas reconnu en tant que commande interne
    ou externe, un programme ex?cutable ou un fichier de commandes.

    Note that the path of oracle bin is present in the enviroment variables.

    Can you tell me what wrong ?

    For the second approch, I've implemented as following

    process->setStandardOutputFile(QString("%1\\exec_script_%2.log").arg(script_path.replace("/","\\"), script_name));
    		argList << QString("%1/%2@%3 @\"%4\\%5\"").arg(m_sDbUser, m_sDbPwd, m_sDbName, script_path.replace("/","\\"), script_name);
    		process->startDetached("sqlplus", argList);

    but no log file was created.

    Can you tell me what wrong and how to fix this.

    Really many thanks.

  • Lifetime Qt Champion


    For your tests, you should use the full path to the executable. You can check after that the state of the PATH environment variable.

    For your paths, use forward slashes in your code and then QDir::toNativeSeparators. That will make things easier to write.

  • @mourad_bilog
    Do all things @SGaist says. I don't think startDetached() is right, it may interfere with either redirection or certainly waitForFinished() I would have thought. Test your stuff a bit at a time. The principle of redirection does work.

  • Hello,
    Many thanks @SGaist, @JonB for your contribution and very helpfull responses.

    now, the output log is ok. I've juste one thing to resolve. In fact, when running sqlplus without to full path, I've an error that this file is not found or not existing noting that the oracle bin path is indicated in the envirement path.
    Can you tell me why I've this error and what I must to change to fix this problem.

    Many thanks in advance.

  • @mourad_bilog
    How do you run this sqlplus completely outside of Qt?

  • Lifetime Qt Champion

    Check the PATH environment variable in the Run part of the Project panel. It likely does not contain the path to sqlplus.

  • @JonB from the Windows bash I run direcly sqlplus without the full path.
    Note that, if I test with the sqlcmd (SQL Server) from Qt application, it work fine without the full path.

    Note that twice pathes are in variables envirenement

  • @mourad_bilog
    What directory is the sqlplus in? How does your PATH variable outside of Qt ()"from the Windows bash I run direcly sqlplus" compare to the PATH when launching your process from within Creator or wherever you run it from? When it does not work via QProcess, what have you done about checking for any error and in particular reporting any process->readAllStandardError() (and readAllStandardOutput())?

  • @JonB sqplus is located in


    Here's the %PATH% output from the Windows command bash :

    echo %PATH%
    D:\app1\Mouadh\product\11.2.0\dbhome_2\bin;C:\ProgramData\Oracle\Java\javapath;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\Wbem;C:\WINDOWS\System32\WindowsPowerShell\v1.0\;C:\Program Files (x86)\Java\jdk1.7.0_09\bin;C:\Program Files (x86)\Java\jre7\bin;C:\Program Files (x86)\Windows Kits\8.0\Windows Performance Toolkit\;C:\Program Files\Microsoft SQL Server\110\Tools\Binn\;

    I'm using MS Vistual Studio and readAllStandardError() (and readAllStandardOutput() return the error "not found or not internal /external / batch command" when I call qprocess start.

  • @mourad_bilog
    So you can see it is finding it from the very first element in your PATH when you execute from " the Windows command bash". I don't know when/where that gets prepended to your PATH? It appears to be the case that your PATH does not have that when you execute it from Creator. @SGaist told you:

    Check the PATH environment variable in the Run part of the Project panel. It likely does not contain the path to sqlplus.

    ? Maybe it gets prepended only when you go into bash shell, e.g. some Windows .bashrc file. So either you have do the same/run it via bash as I showed earlier, or you have to put the necessary into that variable in Creator. Also depends whether your application is for your own use only or whether you intend to distribute it to others.

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