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Re^2: Seeking in a file

by spazm (Monk)
on Jun 02, 2012 at 00:25 UTC ( #973895=note: print w/ replies, xml ) Need Help??


in reply to Re: Seeking in a file
in thread Seeking in a file

Is seeking backwards in a piped stream going to work (reliably)?

This seems like a basic map-reduce paradigm. It would be nice to have a method that would "just work(tm)" for pre sorted data like this.

Something like an iterator over the group of file handles that stores a one line buffer. Hadoop::Streaming::Reducer::Input does something like this for a single filehandle, but its terrible clumsy code (sorry 'bout that).

Hadoop::Streaming::Reducer::Input source.


Comment on Re^2: Seeking in a file
Re^3: Seeking in a file
by choroba (Abbot) on Jun 02, 2012 at 00:29 UTC
    I fear seeking does not work in a piped stream at all. You have to remember tha last line so you can return to it later.

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