That depends on what you would like to do with the single line. Is it text? Is it binary information? If you can process that line piecewise, than you could use sysread for example. Binary information is accessible by unpack after reading the data piecewise. (Updated after JavaFans comment.)
A sliding window that is big enough to hold more characters or bytes than the biggest chunk of information your program needs to process might come handy too.

HTH

In reply to Re: Reading a VERY LARGE file with SINGLE line as content! by Perlbotics
in thread Reading a VERY LARGE file with SINGLE line as content! by biswanath_c

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