[p5sagit/p5-mst-13.2.git] / lib / File / Copy.pm

# File/Copy.pm. Written in 1994 by Aaron Sherman <ajs@ajs.com>. This
# source code has been placed in the public domain by the author.
# Please be kind and preserve the documentation.
#

package File::Copy;

require Exporter;
use Carp;

@ISA=qw(Exporter);
@EXPORT=qw(copy);
@EXPORT_OK=qw(copy cp);

$File::Copy::VERSION = '1.5';
$File::Copy::Too_Big = 1024 * 1024 * 2;

sub VERSION {
    # Version of File::Copy
    return $File::Copy::VERSION;
}

sub copy {
    croak("Usage: copy( file1, file2 [, buffersize]) ")
      unless(@_ == 2 || @_ == 3);

    if (($^O eq 'VMS' or $^O eq 'os2') && ref(\$to) ne 'GLOB' &&
        !(defined ref $to and (ref($to) eq 'GLOB' ||
          ref($to) eq 'FileHandle' || ref($to) eq 'VMS::Stdio')))
        { return File::Copy::syscopy($_[0],$_[1]) }

    my $from = shift;
    my $to = shift;
    my $closefrom=0;
    my $closeto=0;
    my ($size, $status, $r, $buf);
    local(*FROM, *TO);
    local($\) = '';

    if (ref(\$from) eq 'GLOB') {
	*FROM = $from;
    } elsif (defined ref $from and
	     (ref($from) eq 'GLOB' || ref($from) eq 'FileHandle' ||
	      ref($from) eq 'VMS::Stdio')) {
	*FROM = *$from;
    } else {
	open(FROM,"<$from")||goto(fail_open1);
	binmode FROM;
	$closefrom = 1;
    }

    if (ref(\$to) eq 'GLOB') {
	*TO = $to;
    } elsif (defined ref $to and
	     (ref($to) eq 'GLOB' || ref($to) eq 'FileHandle' ||
	      ref($to) eq 'VMS::Stdio')) {
	*TO = *$to;
    } else {
	open(TO,">$to")||goto(fail_open2);
	binmode TO;
	$closeto=1;
    }

    if (@_) {
	$size = shift(@_) + 0;
	croak("Bad buffer size for copy: $size\n") unless ($size > 0);
    } else {
	$size = -s FROM;
	$size = 1024 if ($size < 512);
	$size = $File::Copy::Too_Big if ($size > $File::Copy::Too_Big);
    }

    $buf = '';
    while(defined($r = read(FROM,$buf,$size)) && $r > 0) {
	if (syswrite (TO,$buf,$r) != $r) {
	    goto fail_inner;    
	}
    }
    goto fail_inner unless(defined($r));
    close(TO) || goto fail_open2 if $closeto;
    close(FROM) || goto fail_open1 if $closefrom;
    # Use this idiom to avoid uninitialized value warning.
    return 1;
    
    # All of these contortions try to preserve error messages...
  fail_inner:
    if ($closeto) {
	$status = $!;
	$! = 0;
	close TO;
	$! = $status unless $!;
    }
  fail_open2:
    if ($closefrom) {
	$status = $!;
	$! = 0;
	close FROM;
	$! = $status unless $!;
    }
  fail_open1:
    return 0;
}


*cp = \&copy;
# &syscopy is an XSUB under OS/2
*syscopy = ($^O eq 'VMS' ? \&rmscopy : \&copy) unless $^O eq 'os2';

1;

__END__

=head1 NAME

File::Copy - Copy files or filehandles

=head1 SYNOPSIS

  	use File::Copy;

	copy("file1","file2");
  	copy("Copy.pm",\*STDOUT);'

  	use POSIX;
	use File::Copy cp;

	$n=FileHandle->new("/dev/null","r");
	cp($n,"x");'

=head1 DESCRIPTION

The File::Copy module provides a basic function C<copy> which takes two
parameters: a file to copy from and a file to copy to. Either
argument may be a string, a FileHandle reference or a FileHandle
glob. Obviously, if the first argument is a filehandle of some
sort, it will be read from, and if it is a file I<name> it will
be opened for reading. Likewise, the second argument will be
written to (and created if need be).  Note that passing in
files as handles instead of names may lead to loss of information
on some operating systems; it is recommended that you use file
names whenever possible.

An optional third parameter can be used to specify the buffer
size used for copying. This is the number of bytes from the
first file, that wil be held in memory at any given time, before
being written to the second file. The default buffer size depends
upon the file, but will generally be the whole file (up to 2Mb), or
1k for filehandles that do not reference files (eg. sockets).

You may use the syntax C<use File::Copy "cp"> to get at the
"cp" alias for this function. The syntax is I<exactly> the same.

File::Copy also provides the C<syscopy> routine, which copies the
file specified in the first parameter to the file specified in the
second parameter, preserving OS-specific attributes and file
structure.  For Unix systems, this is equivalent to the simple
C<copy> routine.  For VMS systems, this calls the C<rmscopy>
routine (see below).  For OS/2 systems, this calls the C<syscopy>
XSUB directly.

=head2 Special behavior under VMS

If the second argument to C<copy> is not a file handle for an
already opened file, then C<copy> will perform an RMS copy of
the input file to a new output file, in order to preserve file
attributes, indexed file structure, I<etc.>  The buffer size
parameter is ignored.  If the second argument to C<copy> is a
Perl handle to an opened file, then data is copied using Perl
operators, and no effort is made to preserve file attributes
or record structure.

The RMS copy routine may also be called directly under VMS
as C<File::Copy::rmscopy> (or C<File::Copy::syscopy>, which
is just an alias for this routine).

=item rmscopy($from,$to[,$date_flag])

The first and second arguments may be strings, typeglobs, or
typeglob references; they are used in all cases to obtain the
I<filespec> of the input and output files, respectively.  The
name and type of the input file are used as defaults for the
output file, if necessary.

A new version of the output file is always created, which
inherits the structure and RMS attributes of the input file,
except for owner and protections (and possibly timestamps;
see below).  All data from the input file is copied to the
output file; if either of the first two parameters to C<rmscopy>
is a file handle, its position is unchanged.  (Note that this
means a file handle pointing to the output file will be
associated with an old version of that file after C<rmscopy>
returns, not the newly created version.)

The third parameter is an integer flag, which tells C<rmscopy>
how to handle timestamps.  If it is E<lt> 0, none of the input file's
timestamps are propagated to the output file.  If it is E<gt> 0, then
it is interpreted as a bitmask: if bit 0 (the LSB) is set, then
timestamps other than the revision date are propagated; if bit 1
is set, the revision date is propagated.  If the third parameter
to C<rmscopy> is 0, then it behaves much like the DCL COPY command:
if the name or type of the output file was explicitly specified,
then no timestamps are propagated, but if they were taken implicitly
from the input filespec, then all timestamps other than the
revision date are propagated.  If this parameter is not supplied,
it defaults to 0.

Like C<copy>, C<rmscopy> returns 1 on success.  If an error occurs,
it sets C<$!>, deletes the output file, and returns 0.

=head1 RETURN

Returns 1 on success, 0 on failure. $! will be set if an error was
encountered.

=head1 AUTHOR

File::Copy was written by Aaron Sherman I<E<lt>ajs@ajs.comE<gt>> in 1995.
The VMS-specific code was added by Charles Bailey
I<E<lt>bailey@genetics.upenn.eduE<gt>> in March 1996.

=cut
Commit	Line	Data
f716a1dd	1	# File/Copy.pm. Written in 1994 by Aaron Sherman <ajs@ajs.com>. This
	2	# source code has been placed in the public domain by the author.
	3	# Please be kind and preserve the documentation.
	4	#
	5
	6	package File::Copy;
	7
	8	require Exporter;
	9	use Carp;
	10
	11	@ISA=qw(Exporter);
	12	@EXPORT=qw(copy);
	13	@EXPORT_OK=qw(copy cp);
	14
	15	$File::Copy::VERSION = '1.5';
	16	$File::Copy::Too_Big = 1024 * 1024 * 2;
	17
	18	sub VERSION {
	19	# Version of File::Copy
	20	return $File::Copy::VERSION;
	21	}
	22
	23	sub copy {
	24	croak("Usage: copy( file1, file2 [, buffersize]) ")
	25	unless(@_ == 2 \|\| @_ == 3);
	26
9b957b78	27	if (($^O eq 'VMS' or $^O eq 'os2') && ref(\$to) ne 'GLOB' &&
	28	!(defined ref $to and (ref($to) eq 'GLOB' \|\|
	29	ref($to) eq 'FileHandle' \|\| ref($to) eq 'VMS::Stdio')))
	30	{ return File::Copy::syscopy($_[0],$_[1]) }
a5f75d66	31
f716a1dd	32	my $from = shift;
f716a1dd	33	my $to = shift;
f716a1dd	34	my $closefrom=0;
	35	my $closeto=0;
	36	my ($size, $status, $r, $buf);
	37	local(FROM, TO);
48a5c399	38	local($\) = '';
f716a1dd	39
	40	if (ref(\$from) eq 'GLOB') {
	41	*FROM = $from;
	42	} elsif (defined ref $from and
9b957b78	43	(ref($from) eq 'GLOB' \|\| ref($from) eq 'FileHandle' \|\|
9b957b78	44	ref($from) eq 'VMS::Stdio')) {
f716a1dd	45	FROM = $from;
	46	} else {
	47	open(FROM,"<$from")\|\|goto(fail_open1);
9b957b78	48	binmode FROM;
f716a1dd	49	$closefrom = 1;
	50	}
	51
	52	if (ref(\$to) eq 'GLOB') {
	53	*TO = $to;
	54	} elsif (defined ref $to and
9b957b78	55	(ref($to) eq 'GLOB' \|\| ref($to) eq 'FileHandle' \|\|
9b957b78	56	ref($to) eq 'VMS::Stdio')) {
f716a1dd	57	TO = $to;
	58	} else {
	59	open(TO,">$to")\|\|goto(fail_open2);
9b957b78	60	binmode TO;
f716a1dd	61	$closeto=1;
	62	}
	63
	64	if (@_) {
	65	$size = shift(@_) + 0;
	66	croak("Bad buffer size for copy: $size\n") unless ($size > 0);
	67	} else {
	68	$size = -s FROM;
	69	$size = 1024 if ($size < 512);
	70	$size = $File::Copy::Too_Big if ($size > $File::Copy::Too_Big);
	71	}
	72
	73	$buf = '';
	74	while(defined($r = read(FROM,$buf,$size)) && $r > 0) {
	75	if (syswrite (TO,$buf,$r) != $r) {
	76	goto fail_inner;
	77	}
	78	}
	79	goto fail_inner unless(defined($r));
	80	close(TO) \|\| goto fail_open2 if $closeto;
	81	close(FROM) \|\| goto fail_open1 if $closefrom;
48a5c399	82	# Use this idiom to avoid uninitialized value warning.
f716a1dd	83	return 1;
	84
	85	# All of these contortions try to preserve error messages...
	86	fail_inner:
	87	if ($closeto) {
	88	$status = $!;
	89	$! = 0;
	90	close TO;
	91	$! = $status unless $!;
	92	}
	93	fail_open2:
	94	if ($closefrom) {
	95	$status = $!;
	96	$! = 0;
	97	close FROM;
	98	$! = $status unless $!;
	99	}
	100	fail_open1:
f716a1dd	101	return 0;
f716a1dd	102	}
9b957b78	103
9b957b78	104
f716a1dd	105	*cp = \©
9b957b78	106	# &syscopy is an XSUB under OS/2
9b957b78	107	*syscopy = ($^O eq 'VMS' ? \&rmscopy : \&copy) unless $^O eq 'os2';
f716a1dd	108
	109	1;
	110
	111	__END__
a5f75d66	112
f716a1dd	113	=head1 NAME
	114
	115	File::Copy - Copy files or filehandles
	116
a5f75d66	117	=head1 SYNOPSIS
f716a1dd	118
	119	use File::Copy;
	120
	121	copy("file1","file2");
	122	copy("Copy.pm",\*STDOUT);'
	123
	124	use POSIX;
	125	use File::Copy cp;
	126
	127	$n=FileHandle->new("/dev/null","r");
	128	cp($n,"x");'
	129
	130	=head1 DESCRIPTION
	131
9b957b78	132	The File::Copy module provides a basic function C<copy> which takes two
f716a1dd	133	parameters: a file to copy from and a file to copy to. Either
	134	argument may be a string, a FileHandle reference or a FileHandle
	135	glob. Obviously, if the first argument is a filehandle of some
	136	sort, it will be read from, and if it is a file I<name> it will
	137	be opened for reading. Likewise, the second argument will be
9b957b78	138	written to (and created if need be). Note that passing in
	139	files as handles instead of names may lead to loss of information
	140	on some operating systems; it is recommended that you use file
	141	names whenever possible.
f716a1dd	142
	143	An optional third parameter can be used to specify the buffer
	144	size used for copying. This is the number of bytes from the
	145	first file, that wil be held in memory at any given time, before
	146	being written to the second file. The default buffer size depends
	147	upon the file, but will generally be the whole file (up to 2Mb), or
	148	1k for filehandles that do not reference files (eg. sockets).
	149
	150	You may use the syntax C<use File::Copy "cp"> to get at the
	151	"cp" alias for this function. The syntax is I<exactly> the same.
	152
9b957b78	153	File::Copy also provides the C<syscopy> routine, which copies the
	154	file specified in the first parameter to the file specified in the
	155	second parameter, preserving OS-specific attributes and file
	156	structure. For Unix systems, this is equivalent to the simple
	157	C<copy> routine. For VMS systems, this calls the C<rmscopy>
	158	routine (see below). For OS/2 systems, this calls the C<syscopy>
	159	XSUB directly.
	160
	161	=head2 Special behavior under VMS
	162
	163	If the second argument to C<copy> is not a file handle for an
	164	already opened file, then C<copy> will perform an RMS copy of
	165	the input file to a new output file, in order to preserve file
	166	attributes, indexed file structure, I<etc.> The buffer size
	167	parameter is ignored. If the second argument to C<copy> is a
	168	Perl handle to an opened file, then data is copied using Perl
	169	operators, and no effort is made to preserve file attributes
	170	or record structure.
	171
	172	The RMS copy routine may also be called directly under VMS
	173	as C<File::Copy::rmscopy> (or C<File::Copy::syscopy>, which
	174	is just an alias for this routine).
	175
	176	=item rmscopy($from,$to[,$date_flag])
	177
	178	The first and second arguments may be strings, typeglobs, or
	179	typeglob references; they are used in all cases to obtain the
	180	I<filespec> of the input and output files, respectively. The
	181	name and type of the input file are used as defaults for the
	182	output file, if necessary.
	183
	184	A new version of the output file is always created, which
	185	inherits the structure and RMS attributes of the input file,
	186	except for owner and protections (and possibly timestamps;
	187	see below). All data from the input file is copied to the
	188	output file; if either of the first two parameters to C<rmscopy>
	189	is a file handle, its position is unchanged. (Note that this
	190	means a file handle pointing to the output file will be
	191	associated with an old version of that file after C<rmscopy>
	192	returns, not the newly created version.)
	193
	194	The third parameter is an integer flag, which tells C<rmscopy>
1fef88e7	195	how to handle timestamps. If it is E<lt> 0, none of the input file's
1fef88e7	196	timestamps are propagated to the output file. If it is E<gt> 0, then
9b957b78	197	it is interpreted as a bitmask: if bit 0 (the LSB) is set, then
	198	timestamps other than the revision date are propagated; if bit 1
	199	is set, the revision date is propagated. If the third parameter
	200	to C<rmscopy> is 0, then it behaves much like the DCL COPY command:
	201	if the name or type of the output file was explicitly specified,
	202	then no timestamps are propagated, but if they were taken implicitly
	203	from the input filespec, then all timestamps other than the
	204	revision date are propagated. If this parameter is not supplied,
	205	it defaults to 0.
	206
	207	Like C<copy>, C<rmscopy> returns 1 on success. If an error occurs,
	208	it sets C<$!>, deletes the output file, and returns 0.
	209
f716a1dd	210	=head1 RETURN
	211
	212	Returns 1 on success, 0 on failure. $! will be set if an error was
	213	encountered.
	214
	215	=head1 AUTHOR
	216
9b957b78	217	File::Copy was written by Aaron Sherman I<E<lt>ajs@ajs.comE<gt>> in 1995.
	218	The VMS-specific code was added by Charles Bailey
	219	I<E<lt>bailey@genetics.upenn.eduE<gt>> in March 1996.
f716a1dd	220
f716a1dd	221	=cut