As a one-liner: 

perl -s -nle"BEGIN{open BIG};($undef,$l)=split;read BIG,$data,$l;print
+ $data" -- 
-BIG=bigfile.dat index.dat > outfile.dat

[download]

All one one line. Switch "s to 's on *nix.

Update: A slightly shorter version

perl -sple"BEGIN{open BIG};($undef,$l)=split;read(BIG,$_,$l)" -- 
-BIG=bigfile.dat index.dat >outfile.dat

[download]
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In reply to Re: Read offset into other files by BrowserUk
in thread Read offset into other files by gio001

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