Hi

lets say I wanted a sliding window to search a file from end to start.²

Could do this with seek and read in a loop.

Now is seek operating on byte boundaries ,but read depends on the encryption layer. °

What's the best way than to read an encoded file, like in UTF-8, backwards ?

Is read fail-proof when accidentally starting inside a wide character after a seek?

Or is it better to open :raw and to search the next character (or line) boundary manually and to decode with Encode then?

I'm aware of File::ReadBackwards , but want to understand the mechanisms better and operate on windows and not lines.

Cheers Rolf
(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery FootballPerl is like chess, only without the dice

updates
°) 
  DB<1> open $fh,'<','input2'

  DB<2> read $fh => $in, 100

  DB<3> p tell $fh
114                            # surprise
  DB<4> open $fh,'<:raw','input2'

  DB<5> p tell $fh
0
  DB<6> read $fh => $in, 100

  DB<7> p tell $fh
100
  DB<8>

[download]

²) I've been asked what I mean with "sliding window", please see this sliding window description. There I start from the beginning, but it's often favorable to start from the end. (choroba++ for pm'ing me)

In reply to Processing an encoded file backwards by LanX

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