Concatenation of several large files

[Gafur]

I am under Cygwin. I saw lots of different ways to proceed with the operation of concatenation of files on the net. I wonder which is the fastest and least likely to be hampered by large file sizes of input and output.

open(OUT, ">> $output") or die("Can't create output file: $!");
binmode(OUT);
foreach (@files) {
      open(IN, "< $_")
      or die("Can't open input file $_: $!");
      binmode(IN);
      {
           local $_;
           print OUT $_ while <IN>;
      }
}

[void]

This method is good. Small corrections

open(OUT, '>' $output) or die("Can't create output file: $!");
binmode OUT;
foreach (@files) {
      open(IN, '<', $_) or die("Can't open input file $_: $!");
      binmode IN;
      print OUT $_ while (<IN>);
      close(IN);
}
close(OUT);

[Gafur]

Thank you for your help and it worked! One more thing, which is faster methods: using the shell as a "cat" or "copy"?

[Reegan]

copy => Makes a copy, and so do not allow the concatenation. This is not its goal.
cat => Displays on the screen, but then it loses in performance and its goal is not concatenation.

[void]

cat - Concatenate files and displays them on standard output.

Syntax

cat [-benstuvAET] [--number] [--number-nonblank] [--squeeze-blank] [--show-nonprinting] [--show-ends] [--show-tabs] [--show-all] [--help] [--version] [file...]

Description

cat displays the standard output content of each file (or the contents of the coming standard if no filename is provided, or if the name `- 'is specified).

Parameters

-b, --number-nonblank
Nonblank number output, starting with 1.
-e
Equivalent to -vE.
-n, --number
Sorted output, starting with 1.
-s, --squeeze-blank
Replace multiple blank lines with a single blank line.
-t
Equivalent to -vT.
-u
No effect - for Unix compatibility only.
-v, --show-nonprinting
Show control characters, Show romanization
`^', and prefixed with `M-' the characters with the eighth bit set.
-A, --show-all
Equivalent to -vET.
-E, --show-ends
Show a `$' at the end of each line.
-T, --show-tabs
Displays the TAB character so: `^I'.
--help
Display a help message on standard output and exit normally.
--version
Show version number to stdout and exit normally.