Reading from a file not line-by-line

c++, file, filesystems, performance, qt

Solution

QTextStream has a ReadAll function:

http://doc.qt.io/qt-4.8/qtextstream.html#readAll

Surely that's all you need?

Or you could read all into the QByteArray and QTextStream can take that as an input instead of a QFile.

Problem

Assigning a `QTextStream` to a `QFile` and reading it line-by-line is easy and works fine, but I wonder if the performance can be inreased by first storing the file in memory and then processing it line-by-line. Using FileMon from sysinternals, I've encountered that the file is read in chunks of 16KB and since the files I've to process are not that big (~2MB, but many!), loading them into memory would be a nice thing to try. Any ideas how can I do so? `QFile` is inhereted from `QIODevice`, which allows me to `ReadAll()` it into `QByteArray`, but how to proceed then and divide it into lines?

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