Common sense tells us that reading the file with Perl would be much faster than launching an entirely new process, reading the file, dumping it to STDOUT and then reading it from there. But just to be sure, whenever you want to find out which thing is faster, fire up Benchmark. 

perl -MBenchmark -e 'timethese( 1000, 
  { cat => sub { my $str = qx|cat /usr/share/dict/words|; }, 
read => sub { local $/; open my $f, "/usr/share/dict/words" 
or die $!; my $str = <$f>; } } )'
Benchmark: timing 1000 iterations of cat, read...
  cat:  6 wallclock secs ( 1.69 usr  1.34 sys +  0.28 cusr  
2.34 csys =  5.65 CPU) @ 330.03/s (n=1000)
  read:  1 wallclock secs ( 0.58 usr +  0.58 sys =  1.16 
CPU) @ 862.07/s (n=1000)

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In reply to Re: shell vs. filehandler by friedo
in thread shell vs. filehandler by 10basetom

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