File::Copy::Recursive::Reduced(3) User Contributed Perl Documentation
NAME
File::Copy::Recursive::Reduced - Recursive copying of files and
directories within Perl 5 toolchain
SYNOPSIS
use File::Copy::Recursive::Reduced qw(fcopy dircopy);
fcopy($orig,$new) or die $!;
dircopy($orig,$new) or die $!;
DESCRIPTION
This library is intended as a not-quite-drop-in replacement for certain
functionality provided by CPAN distribution File-Copy-Recursive
. The library
provides methods similar enough to that distribution's fcopy(),
dircopy() and rcopy() functions to be usable in those CPAN
distributions often described as being part of the Perl toolchain.
Rationale
File::Copy::Recursive (hereinafter referred to as FCR) is heavily used
in other CPAN libraries. Out of over 30,000 other CPAN distributions
studied in early 2018, it ranks by one calculation as the 129th highest
distribution in terms of its total direct and indirect reverse
dependencies. In current parlance, it sits "high upstream on the CPAN
river." Hence, it ought to work correctly and be installable on all
operating systems where Perl is well supported.
However, as of early April 2018, FCR version 0.40 wass failing to pass
its tests against either Perl 5.26 or Perl 5 blead on important
operating systems including Windows, FreeBSD and NetBSD
().
As a consequence, CPAN installers such as cpan and cpanm were failing
to install it (unless one resorted to the "--force" option). This
prevented distributions dependent (directly or indirectly) on FCR from
being installed as well.
Some patches had been provided to the FCR bug tracker
for
this problem. However, as late as April 18 2018 those patches had not
yet been applied. This posed a critical problem for the ability to
assess the impact of the soon-to-be-released perl-5.28.0 on CPAN
distributions (the so-called "Blead Breaks CPAN" ("BBC") problem) on
platforms other than Linux.
File::Copy::Recursive::Reduced (hereinafter referred to as FCR2) is
intended to provide a minimal subset of FCR's functionality -- just
enough to get the Perl toolchain working on the platforms where FCR is
currently failing. Functions will be added to FCR2 only insofar as
investigation shows that they can replace usage of FCR functions in
toolchain and other heavily used modules. No attempt will be made to
reproduce all the functionality currently provided or claimed to be
provided by FCR.
On April 19 2018, FCR's author, Daniel Muey, released version 0.41 to
CPAN. This version included a patch submitted by Tom Hukins which
corrected the problem addressed by FCR2. FCR once again built and
tested correctly on FreeBSD. That meant that its 6000-plus reverse
dependencies can once again be reached by cpan and other installers.
That in turn means that we can conduct exhaustive BBC investigations on
FreeBSD and other platforms.
With that correction in FCR, the original rationale for FCR2 has been
superseded. I will continue to maintain the code and respond to bug
reports, but am suspending active development. I now deem FCR2
feature-complete.
SUBROUTINES
The current version of FCR2 provides three exportable and publicly
supported subroutines partially equivalent to the similarly named
subroutines exported by FCR.
fcopy()
o Purpose
A stripped-down replacement for File::Copy::Recursive::fcopy().
Copies a file to a new location, recursively creating directories
as needed. Does not copy directories. Unlike File::Copy::copy(),
fcopy() attempts to preserve the mode of the original file.
o Arguments
fcopy($orig, $new) or die $!;
List of two required arguments:
o Absolute path to the file being copied; and
o Absolute path to the location to which the file is being
copied.
Four cases should be noted:
1 Create copy within same directory but new basename
fcopy('/path/to/filename', '/path/to/newfile');
The second argument must be the absolute path to the new file.
(Otherwise the file will be created in the current working
directory, which is almost certainly what you do not want.)
2 Create copy within different, already existing directory, same
basename
fcopy('/path/to/filename', '/path/to/existing/directory');
The second argument can be merely the path to the existing
directory; will create /path/to/existing/directory/filename.
3 Create copy within different, not yet existing directory, same
basename
fcopy('/path/to/filename', '/path/not/yet/existing/directory/filename');
The second argument will be interpreted as the complete path to
the newly created file. The basename must be included even if
it is the same as in the first argument. Will create
/path/not/yet/existing/directory/filename.
4 Create copy within different, not yet existing directory,
different basename
fcopy('/path/to/filename', '/path/not/yet/existing/directory/newfile');
The second argument will be interpreted as the complete path to
the newly created file. Will create
/path/not/yet/existing/directory/newfile.
o Return Value
Returns 1 upon success; 0 upon failure. Returns an undefined value
if, for example, function cannot validate arguments.
o Comment
Since fcopy() internally uses File::Copy::copy() to perform the
copying, the arguments are subject to the same qualifications as
that function's arguments. Call perldoc File::Copy for discussion
of those arguments.
dircopy()
o Purpose
A stripped-down replacement for File::Copy::Recursive::dircopy().
Given the path to the directory specified by the first argument,
the function copies all of the files and directories beneath it to
the directory specified by the second argument.
o Arguments
my $count = dircopy($orig, $new);
warn "dircopy() returned undefined value" unless defined $count;
o Return Value
Upon completion, returns the count of directories and files created
-- which might be 0.
Should the function not complete (but not "die"), an undefined
value will be returned. That generally indicates problems with
argument validation. This approach is taken for consistency with
File::Copy::Recursive::dircopy().
In list context the return value is a one-item list holding the
same value as returned in scalar context. The three-item list
return value of File::Copy::Recursive::dircopy() is not supported.
o Restrictions
None of "File::Copy::Recursive::dircopy"'s bells and whistles. No
guaranteed preservation of file or directory modes. No restriction
on maximum depth. No nothing; this is fine-tuned to the needs of
Perl toolchain modules and their test suites.
rcopy()
o Purpose
A stripped-down replacement for File::Copy::Recursive::rcopy(). As
is the case with that FCR function, rcopy() is more or less a
wrapper around fcopy() or dircopy(), depending on the nature of the
first argument.
o Arguments
rcopy($orig, $new) or die $!;
List of two required arguments:
o Absolute path to the entity (file or directory) being copied;
and
o Absolute path to the location to which the entity is being
copied.
o Return Value
Returns 1 upon success; 0 upon failure. Returns an undefined value
if, for example, function cannot validate arguments.
o Comment
Please read the documentation for fcopy() or dircopy(), depending
on the nature of the first argument.
File::Copy::Recursive Subroutines Not Supported in
File::Copy::Recursive::Reduced
As of the current version, FCR2 has no publicly documented, exportable
subroutines equivalent to the following FCR exportable subroutines:
rcopy_glob
fmove
rmove
rmove_glob
dirmove
pathempty
pathrm
pathrmdir
Consideration is being given to supporting rcopy().
BUGS AND SUPPORT
Please report any bugs by mail to
"bug-File-Copy-Recursive-Reduced@rt.cpan.org" or through the web
interface at .
ACKNOWLEDGEMENTS
Notwithstanding the fact that this distribution is being released to
address certain problems in File-Copy-Recursive, credit must be given
to FCR author Daniel Muey
for ingenious conception and execution. The implementation of the
subroutines provided by FCR2 follows that found in FCR to a significant
extent.
Thanks also to Tom Hukins for supplying the patch which corrects FCR's
problems and which has been incorporated into FCR2 as well.
Thanks to Hakon Haegland for paying attention to how this library
performs on Windows and other platforms to which the author does not
have access.
AUTHOR
James E Keenan
CPAN ID: JKEENAN
jkeenan@cpan.org
http://thenceforward.net/perl
COPYRIGHT
This program is free software; you can redistribute it and/or modify it
under the same terms as Perl itself.
The full text of the license can be found in the LICENSE file included
with this module.
Copyright James E Keenan 2018-2023. All rights reserved.
SEE ALSO
perl(1). File::Copy::Recursive(3).
perl v5.38.2 2024-05-05 File::Copy::Recursive::Reduced(3)