[Qt-interest] Is there any hope for the pos() method when used with a QTextStream?

[Atlant Schmidt]

Folks:

  So I wrote this wonderful algorithm that ought to let my users page
  their way forwards and backwards through this huge text file of
  Open Source licensing information that we maintain. You know
  the drill: "This device uses Open Source software licensed under
  various licenses and we'll now bore you to tears listing them all..."

  I wrote this algorithm using a QTextStream and readLine(), and as
  I read forward through my file, I attempted to save the byte offset
  that would represent the start of each page of licensing info; these
  byte offsets ought to let me easily seek() back to a previous page.
  I obtained those byte offsets by calling myTextStream_ptr->pos().

  Unfortunately, after the first page or two, not only does that *NOT*
  give me valid byte offsets, but it also screws up the reading process
  so that 1) the readLine() operations don't give me the expected data
  and 2) I never reach End-of-File.

  And this is apparently a well-known problem: On Googling, I quickly
  found:

     o https://bugreports.qt.nokia.com/browse/QTBUG-9814<https://bugreports.qt.nokia.com/browse/QTBUG-9814?page=com.atlassian.jira.plugin.system.issuetabpanels%3Acomment-tabpanel>

  and

     o https://bugreports.qt.nokia.com/browse/QTBUG-9989

  both of which seem to directly relate to this problem and neither of
  which are fixed nor have they seen any action in a long time.

  So, is there any hope for me? I already keep a line count so when I need
  to page backwards, I *COULD* close and re-open the file and then read
  forward to the new position that I want, but that seems like using a punch
  card solution in the smartphone age*. Has QTextStream::pos()  been fixed?
  If not, can it be fixed? And if it isn't/can't, has anyone got any better ideas
  for alternatives? (I'd prefer not to keep several tens of thousands of lines
  of text in an array of QStrings in memory, although that would work too.)

                                              Atlant


*And unlike QTextStream, even magtapes implemented a rewind()
  operation.


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