Convertion from QString to unsigned char *

[tbscope]

ucTest = (unsigned char *) str.toLatin1().data();

ucTest = (unsigned char *) str.toLatin1().data();

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Nope, that is not correct.

QString::data() doesn't return what you think it returns.
Use this instead:

ucTest = (unsigned char *) str.toAscii().data();

ucTest = (unsigned char *) str.toAscii().data();

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