[p5sagit/p5-mst-13.2.git] / lib / ExtUtils / Install.pm

package ExtUtils::Install;

$VERSION = substr q$Revision: 1.15 $, 10;
# $Date: 1996/09/03 21:58:58 $

use Exporter;
use Carp ();
use Config ();
use vars qw(@ISA @EXPORT $VERSION);
@ISA = ('Exporter');
@EXPORT = ('install','uninstall','pm_to_blib');
$Is_VMS = $^O eq 'VMS';

my $splitchar = $^O eq 'VMS' ? '|' : $^O eq 'os2' ? ';' : ':';
my @PERL_ENV_LIB = split $splitchar, defined $ENV{'PERL5LIB'} ? $ENV{'PERL5LIB'} : $ENV{'PERLLIB'};
my $Inc_uninstall_warn_handler;

#use vars qw( @EXPORT @ISA $Is_VMS );
#use strict;

sub forceunlink {
    chmod 0666, $_[0];
    unlink $_[0] or Carp::croak("Cannot forceunlink $_[0]: $!")
}

sub install {
    my($hash,$verbose,$nonono,$inc_uninstall) = @_;
    $verbose ||= 0;
    $nonono  ||= 0;

    use Cwd qw(cwd);
    use ExtUtils::MakeMaker; # to implement a MY class
    use File::Basename qw(dirname);
    use File::Copy qw(copy);
    use File::Find qw(find);
    use File::Path qw(mkpath);

    my(%hash) = %$hash;
    my(%pack, %write, $dir, $warn_permissions);
    local(*DIR, *P);
    for (qw/read write/) {
	$pack{$_}=$hash{$_};
	delete $hash{$_};
    }
    my($source_dir_or_file);
    foreach $source_dir_or_file (sort keys %hash) {
	#Check if there are files, and if yes, look if the corresponding
	#target directory is writable for us
	opendir DIR, $source_dir_or_file or next;
	for (readdir DIR) {
	    next if $_ eq "." || $_ eq ".." || $_ eq ".exists";
	    if (-w $hash{$source_dir_or_file} || mkpath($hash{$source_dir_or_file})) {
		last;
	    } else {
		warn "Warning: You do not have permissions to install into $hash{$source_dir_or_file}"
		    unless $warn_permissions++;
	    }
	}
	closedir DIR;
    }
    if (-f $pack{"read"}) {
	open P, $pack{"read"} or Carp::croak("Couldn't read $pack{'read'}");
	# Remember what you found
	while (<P>) {
	    chomp;
	    $write{$_}++;
	}
	close P;
    }
    my $cwd = cwd();
    my $umask = umask 0 unless $Is_VMS;

    # This silly reference is just here to be able to call MY->catdir
    # without a warning (Waiting for a proper path/directory module,
    # Charles!)
    my $MY = {};
    bless $MY, 'MY';
    my($source);
    MOD_INSTALL: foreach $source (sort keys %hash) {
	#copy the tree to the target directory without altering
	#timestamp and permission and remember for the .packlist
	#file. The packlist file contains the absolute paths of the
	#install locations. AFS users may call this a bug. We'll have
	#to reconsider how to add the means to satisfy AFS users also.
	chdir($source) or next;
	find(sub {
	    my ($dev,$ino,$mode,$nlink,$uid,$gid,$rdev,$size,
                         $atime,$mtime,$ctime,$blksize,$blocks) = stat;
	    return unless -f _;
	    return if $_ eq ".exists";
	    my $targetdir = $MY->catdir($hash{$source},$File::Find::dir);
	    my $targetfile = $MY->catfile($targetdir,$_);

	    my $diff = 0;
	    if ( -f $targetfile && -s _ == $size) {
		# We have a good chance, we can skip this one
		$diff = my_cmp($_,$targetfile);
	    } else {
		print "$_ differs\n" if $verbose>1;
		$diff++;
	    }

	    if ($diff){
		if (-f $targetfile){
		    forceunlink($targetfile) unless $nonono;
		} else {
		    mkpath($targetdir,0,0755) unless $nonono;
		    print "mkpath($targetdir,0,0755)\n" if $verbose>1;
		}
		copy($_,$targetfile) unless $nonono;
		print "Installing $targetfile\n";
		utime($atime,$mtime + $Is_VMS,$targetfile) unless $nonono>1;
		print "utime($atime,$mtime,$targetfile)\n" if $verbose>1;
		$mode = 0444 | ( $mode & 0111 ? 0111 : 0 );
		chmod $mode, $targetfile;
		print "chmod($mode, $targetfile)\n" if $verbose>1;
	    } else {
		print "Skipping $targetfile (unchanged)\n" if $verbose;
	    }
	    
	    if (! defined $inc_uninstall) { # it's called 
	    } elsif ($inc_uninstall == 0){
		inc_uninstall($_,$File::Find::dir,$verbose,1); # nonono set to 1
	    } else {
		inc_uninstall($_,$File::Find::dir,$verbose,0); # nonono set to 0
	    }
	    $write{$targetfile}++;

	}, ".");
	chdir($cwd) or Carp::croak("Couldn't chdir to $cwd: $!");
    }
    umask $umask unless $Is_VMS;
    if ($pack{'write'}) {
	$dir = dirname($pack{'write'});
	mkpath($dir,0,0755);
	print "Writing $pack{'write'}\n";
	open P, ">$pack{'write'}" or Carp::croak("Couldn't write $pack{'write'}: $!");
	for (sort keys %write) {
	    print P "$_\n";
	}
	close P;
    }
}

sub my_cmp {
    my($one,$two) = @_;
    local(*F,*T);
    my $diff = 0;
    open T, $two or return 1;
    open F, $one or Carp::croak("Couldn't open $one: $!");
    my($fr, $tr, $fbuf, $tbuf, $size);
    $size = 1024;
    # print "Reading $one\n";
    while ( $fr = read(F,$fbuf,$size)) {
	unless (
		$tr = read(T,$tbuf,$size) and 
		$tbuf eq $fbuf
	       ){
	    # print "diff ";
	    $diff++;
	    last;
	}
	# print "$fr/$tr ";
    }
    # print "\n";
    close F;
    close T;
    $diff;
}

sub uninstall {
    my($fil,$verbose,$nonono) = @_;
    die "no packlist file found: $fil" unless -f $fil;
    # my $my_req = $self->catfile(qw(auto ExtUtils Install forceunlink.al));
    # require $my_req; # Hairy, but for the first
    local *P;
    open P, $fil or Carp::croak("uninstall: Could not read packlist file $fil: $!");
    while (<P>) {
	chomp;
	print "unlink $_\n" if $verbose;
	forceunlink($_) unless $nonono;
    }
    print "unlink $fil\n" if $verbose;
    forceunlink($fil) unless $nonono;
}

sub inc_uninstall {
    my($file,$libdir,$verbose,$nonono) = @_;
    my($dir);
    my $MY = {};
    bless $MY, 'MY';
    my %seen_dir = ();
    foreach $dir (@INC, @PERL_ENV_LIB, @Config::Config{qw/archlibexp privlibexp sitearchexp sitelibexp/}) {
	next if $dir eq ".";
	next if $seen_dir{$dir}++;
	my($targetfile) = $MY->catfile($dir,$libdir,$file);
	next unless -f $targetfile;

	# The reason why we compare file's contents is, that we cannot
	# know, which is the file we just installed (AFS). So we leave
	# an identical file in place
	my $diff = 0;
	if ( -f $targetfile && -s _ == -s $file) {
	    # We have a good chance, we can skip this one
	    $diff = my_cmp($file,$targetfile);
	} else {
	    print "#$file and $targetfile differ\n" if $verbose>1;
	    $diff++;
	}

	next unless $diff;
	if ($nonono) {
	    if ($verbose) {
		$Inc_uninstall_warn_handler ||= new ExtUtils::Install::Warn;
		$libdir =~ s|^\./|| ; # That's just cosmetics, no need to port. It looks prettier.
		$Inc_uninstall_warn_handler->add("$libdir/$file",$targetfile);
	    }
	    # if not verbose, we just say nothing
	} else {
	    print "Unlinking $targetfile (shadowing?)\n";
	    forceunlink($targetfile);
	}
    }
}

sub pm_to_blib {
    my($fromto,$autodir) = @_;

    use File::Basename qw(dirname);
    use File::Copy qw(copy);
    use File::Path qw(mkpath);
    use AutoSplit;
    # my $my_req = $self->catfile(qw(auto ExtUtils Install forceunlink.al));
    # require $my_req; # Hairy, but for the first

    my $umask = umask 0022 unless $Is_VMS;
    mkpath($autodir,0,0755);
    foreach (keys %$fromto) {
	next if -f $fromto->{$_} && -M $fromto->{$_} < -M $_;
	unless (my_cmp($_,$fromto->{$_})){
	    print "Skip $fromto->{$_} (unchanged)\n";
	    next;
	}
	if (-f $fromto->{$_}){
	    forceunlink($fromto->{$_});
	} else {
	    mkpath(dirname($fromto->{$_}),0,0755);
	}
	copy($_,$fromto->{$_});
	my($mode,$atime,$mtime) = (stat)[2,8,9];
	utime($atime,$mtime+$Is_VMS,$fromto->{$_});
	chmod(0444 | ( $mode & 0111 ? 0111 : 0 ),$fromto->{$_});
	print "cp $_ $fromto->{$_}\n";
	next unless /\.pm$/;
	autosplit($fromto->{$_},$autodir);
    }
    umask $umask unless $Is_VMS;
}

package ExtUtils::Install::Warn;

sub new { bless {}, shift }

sub add {
    my($self,$file,$targetfile) = @_;
    push @{$self->{$file}}, $targetfile;
}

sub DESTROY {
    my $self = shift;
    my($file,$i,$plural);
    foreach $file (sort keys %$self) {
	$plural = @{$self->{$file}} > 1 ? "s" : "";
	print "## Differing version$plural of $file found. You might like to\n";
	for (0..$#{$self->{$file}}) {
	    print "rm ", $self->{$file}[$_], "\n";
	    $i++;
	}
    }
    $plural = $i>1 ? "all those files" : "this file";
    print "## Running 'make install UNINST=1' will unlink $plural for you.\n";
}

1;

__END__

=head1 NAME

ExtUtils::Install - install files from here to there

=head1 SYNOPSIS

B<use ExtUtils::Install;>

B<install($hashref,$verbose,$nonono);>

B<uninstall($packlistfile,$verbose,$nonono);>

B<pm_to_blib($hashref);>

=head1 DESCRIPTION

Both install() and uninstall() are specific to the way
ExtUtils::MakeMaker handles the installation and deinstallation of
perl modules. They are not designed as general purpose tools.

install() takes three arguments. A reference to a hash, a verbose
switch and a don't-really-do-it switch. The hash ref contains a
mapping of directories: each key/value pair is a combination of
directories to be copied. Key is a directory to copy from, value is a
directory to copy to. The whole tree below the "from" directory will
be copied preserving timestamps and permissions.

There are two keys with a special meaning in the hash: "read" and
"write". After the copying is done, install will write the list of
target files to the file named by C<$hashref-E<gt>{write}>. If there is
another file named by C<$hashref-E<gt>{read}>, the contents of this file will
be merged into the written file. The read and the written file may be
identical, but on AFS it is quite likely, people are installing to a
different directory than the one where the files later appear.

uninstall() takes as first argument a file containing filenames to be
unlinked. The second argument is a verbose switch, the third is a
no-don't-really-do-it-now switch.

pm_to_blib() takes a hashref as the first argument and copies all keys
of the hash to the corresponding values efficiently. Filenames with
the extension pm are autosplit. Second argument is the autosplit
directory.

=cut
Commit	Line	Data
4b6d56d3	1	package ExtUtils::Install;
4b6d56d3	2
cee7b94a	3	$VERSION = substr q$Revision: 1.15 $, 10;
cee7b94a	4	# $Date: 1996/09/03 21:58:58 $
f1387719	5
08ad6bd5	6	use Exporter;
08ad6bd5	7	use Carp ();
f1387719	8	use Config ();
f1387719	9	use vars qw(@ISA @EXPORT $VERSION);
4b6d56d3	10	@ISA = ('Exporter');
08ad6bd5	11	@EXPORT = ('install','uninstall','pm_to_blib');
	12	$Is_VMS = $^O eq 'VMS';
	13
f1387719	14	my $splitchar = $^O eq 'VMS' ? '\|' : $^O eq 'os2' ? ';' : ':';
	15	my @PERL_ENV_LIB = split $splitchar, defined $ENV{'PERL5LIB'} ? $ENV{'PERL5LIB'} : $ENV{'PERLLIB'};
	16	my $Inc_uninstall_warn_handler;
	17
08ad6bd5	18	#use vars qw( @EXPORT @ISA $Is_VMS );
4b6d56d3	19	#use strict;
4b6d56d3	20
f1387719	21	sub forceunlink {
	22	chmod 0666, $_[0];
	23	unlink $_[0] or Carp::croak("Cannot forceunlink $_[0]: $!")
	24	}
08ad6bd5	25
4b6d56d3	26	sub install {
f1387719	27	my($hash,$verbose,$nonono,$inc_uninstall) = @_;
4b6d56d3	28	$verbose \|\|= 0;
4b6d56d3	29	$nonono \|\|= 0;
08ad6bd5	30
	31	use Cwd qw(cwd);
	32	use ExtUtils::MakeMaker; # to implement a MY class
	33	use File::Basename qw(dirname);
	34	use File::Copy qw(copy);
	35	use File::Find qw(find);
	36	use File::Path qw(mkpath);
08ad6bd5	37
4b6d56d3	38	my(%hash) = %$hash;
cee7b94a	39	my(%pack, %write, $dir, $warn_permissions);
4b6d56d3	40	local(DIR, P);
	41	for (qw/read write/) {
	42	$pack{$_}=$hash{$_};
	43	delete $hash{$_};
	44	}
08ad6bd5	45	my($source_dir_or_file);
08ad6bd5	46	foreach $source_dir_or_file (sort keys %hash) {
4b6d56d3	47	#Check if there are files, and if yes, look if the corresponding
4b6d56d3	48	#target directory is writable for us
08ad6bd5	49	opendir DIR, $source_dir_or_file or next;
f1387719	50	for (readdir DIR) {
4b6d56d3	51	next if $_ eq "." \|\| $_ eq ".." \|\| $_ eq ".exists";
08ad6bd5	52	if (-w $hash{$source_dir_or_file} \|\| mkpath($hash{$source_dir_or_file})) {
4b6d56d3	53	last;
4b6d56d3	54	} else {
cee7b94a	55	warn "Warning: You do not have permissions to install into $hash{$source_dir_or_file}"
cee7b94a	56	unless $warn_permissions++;
4b6d56d3	57	}
	58	}
	59	closedir DIR;
	60	}
	61	if (-f $pack{"read"}) {
08ad6bd5	62	open P, $pack{"read"} or Carp::croak("Couldn't read $pack{'read'}");
4b6d56d3	63	# Remember what you found
	64	while (<P>) {
	65	chomp;
	66	$write{$_}++;
	67	}
	68	close P;
	69	}
	70	my $cwd = cwd();
08ad6bd5	71	my $umask = umask 0 unless $Is_VMS;
4b6d56d3	72
	73	# This silly reference is just here to be able to call MY->catdir
	74	# without a warning (Waiting for a proper path/directory module,
08ad6bd5	75	# Charles!)
4b6d56d3	76	my $MY = {};
	77	bless $MY, 'MY';
	78	my($source);
	79	MOD_INSTALL: foreach $source (sort keys %hash) {
	80	#copy the tree to the target directory without altering
	81	#timestamp and permission and remember for the .packlist
	82	#file. The packlist file contains the absolute paths of the
	83	#install locations. AFS users may call this a bug. We'll have
	84	#to reconsider how to add the means to satisfy AFS users also.
	85	chdir($source) or next;
	86	find(sub {
	87	my ($dev,$ino,$mode,$nlink,$uid,$gid,$rdev,$size,
	88	$atime,$mtime,$ctime,$blksize,$blocks) = stat;
	89	return unless -f _;
	90	return if $_ eq ".exists";
	91	my $targetdir = $MY->catdir($hash{$source},$File::Find::dir);
	92	my $targetfile = $MY->catfile($targetdir,$_);
4b6d56d3	93
f1387719	94	my $diff = 0;
4b6d56d3	95	if ( -f $targetfile && -s _ == $size) {
4b6d56d3	96	# We have a good chance, we can skip this one
08ad6bd5	97	$diff = my_cmp($_,$targetfile);
4b6d56d3	98	} else {
	99	print "$_ differs\n" if $verbose>1;
	100	$diff++;
	101	}
	102
	103	if ($diff){
08ad6bd5	104	if (-f $targetfile){
f1387719	105	forceunlink($targetfile) unless $nonono;
08ad6bd5	106	} else {
	107	mkpath($targetdir,0,0755) unless $nonono;
	108	print "mkpath($targetdir,0,0755)\n" if $verbose>1;
	109	}
4b6d56d3	110	copy($_,$targetfile) unless $nonono;
f1387719	111	print "Installing $targetfile\n";
08ad6bd5	112	utime($atime,$mtime + $Is_VMS,$targetfile) unless $nonono>1;
4b6d56d3	113	print "utime($atime,$mtime,$targetfile)\n" if $verbose>1;
f1387719	114	$mode = 0444 \| ( $mode & 0111 ? 0111 : 0 );
4b6d56d3	115	chmod $mode, $targetfile;
	116	print "chmod($mode, $targetfile)\n" if $verbose>1;
	117	} else {
f1387719	118	print "Skipping $targetfile (unchanged)\n" if $verbose;
	119	}
	120
	121	if (! defined $inc_uninstall) { # it's called
	122	} elsif ($inc_uninstall == 0){
	123	inc_uninstall($_,$File::Find::dir,$verbose,1); # nonono set to 1
	124	} else {
	125	inc_uninstall($_,$File::Find::dir,$verbose,0); # nonono set to 0
4b6d56d3	126	}
4b6d56d3	127	$write{$targetfile}++;
	128
	129	}, ".");
08ad6bd5	130	chdir($cwd) or Carp::croak("Couldn't chdir to $cwd: $!");
4b6d56d3	131	}
08ad6bd5	132	umask $umask unless $Is_VMS;
4b6d56d3	133	if ($pack{'write'}) {
	134	$dir = dirname($pack{'write'});
	135	mkpath($dir,0,0755);
	136	print "Writing $pack{'write'}\n";
08ad6bd5	137	open P, ">$pack{'write'}" or Carp::croak("Couldn't write $pack{'write'}: $!");
4b6d56d3	138	for (sort keys %write) {
	139	print P "$_\n";
	140	}
	141	close P;
	142	}
	143	}
	144
08ad6bd5	145	sub my_cmp {
	146	my($one,$two) = @_;
	147	local(F,T);
	148	my $diff = 0;
	149	open T, $two or return 1;
	150	open F, $one or Carp::croak("Couldn't open $one: $!");
	151	my($fr, $tr, $fbuf, $tbuf, $size);
	152	$size = 1024;
	153	# print "Reading $one\n";
	154	while ( $fr = read(F,$fbuf,$size)) {
	155	unless (
	156	$tr = read(T,$tbuf,$size) and
	157	$tbuf eq $fbuf
	158	){
	159	# print "diff ";
	160	$diff++;
	161	last;
	162	}
	163	# print "$fr/$tr ";
	164	}
	165	# print "\n";
	166	close F;
	167	close T;
	168	$diff;
	169	}
	170
4b6d56d3	171	sub uninstall {
	172	my($fil,$verbose,$nonono) = @_;
	173	die "no packlist file found: $fil" unless -f $fil;
f1387719	174	# my $my_req = $self->catfile(qw(auto ExtUtils Install forceunlink.al));
f1387719	175	# require $my_req; # Hairy, but for the first
4b6d56d3	176	local *P;
08ad6bd5	177	open P, $fil or Carp::croak("uninstall: Could not read packlist file $fil: $!");
4b6d56d3	178	while (<P>) {
	179	chomp;
	180	print "unlink $_\n" if $verbose;
f1387719	181	forceunlink($_) unless $nonono;
4b6d56d3	182	}
4b6d56d3	183	print "unlink $fil\n" if $verbose;
f1387719	184	forceunlink($fil) unless $nonono;
	185	}
	186
	187	sub inc_uninstall {
	188	my($file,$libdir,$verbose,$nonono) = @_;
	189	my($dir);
	190	my $MY = {};
	191	bless $MY, 'MY';
	192	my %seen_dir = ();
	193	foreach $dir (@INC, @PERL_ENV_LIB, @Config::Config{qw/archlibexp privlibexp sitearchexp sitelibexp/}) {
	194	next if $dir eq ".";
	195	next if $seen_dir{$dir}++;
	196	my($targetfile) = $MY->catfile($dir,$libdir,$file);
	197	next unless -f $targetfile;
	198
	199	# The reason why we compare file's contents is, that we cannot
	200	# know, which is the file we just installed (AFS). So we leave
	201	# an identical file in place
	202	my $diff = 0;
	203	if ( -f $targetfile && -s _ == -s $file) {
	204	# We have a good chance, we can skip this one
	205	$diff = my_cmp($file,$targetfile);
	206	} else {
	207	print "#$file and $targetfile differ\n" if $verbose>1;
	208	$diff++;
	209	}
	210
	211	next unless $diff;
	212	if ($nonono) {
	213	if ($verbose) {
	214	$Inc_uninstall_warn_handler \|\|= new ExtUtils::Install::Warn;
	215	$libdir =~ s\|^\./\|\| ; # That's just cosmetics, no need to port. It looks prettier.
	216	$Inc_uninstall_warn_handler->add("$libdir/$file",$targetfile);
	217	}
	218	# if not verbose, we just say nothing
	219	} else {
	220	print "Unlinking $targetfile (shadowing?)\n";
	221	forceunlink($targetfile);
	222	}
	223	}
08ad6bd5	224	}
	225
	226	sub pm_to_blib {
	227	my($fromto,$autodir) = @_;
	228
	229	use File::Basename qw(dirname);
	230	use File::Copy qw(copy);
	231	use File::Path qw(mkpath);
	232	use AutoSplit;
f1387719	233	# my $my_req = $self->catfile(qw(auto ExtUtils Install forceunlink.al));
f1387719	234	# require $my_req; # Hairy, but for the first
08ad6bd5	235
	236	my $umask = umask 0022 unless $Is_VMS;
	237	mkpath($autodir,0,0755);
	238	foreach (keys %$fromto) {
	239	next if -f $fromto->{$_} && -M $fromto->{$_} < -M $_;
	240	unless (my_cmp($_,$fromto->{$_})){
	241	print "Skip $fromto->{$_} (unchanged)\n";
	242	next;
	243	}
	244	if (-f $fromto->{$_}){
f1387719	245	forceunlink($fromto->{$_});
08ad6bd5	246	} else {
	247	mkpath(dirname($fromto->{$_}),0,0755);
	248	}
	249	copy($_,$fromto->{$_});
cee7b94a	250	my($mode,$atime,$mtime) = (stat)[2,8,9];
	251	utime($atime,$mtime+$Is_VMS,$fromto->{$_});
	252	chmod(0444 \| ( $mode & 0111 ? 0111 : 0 ),$fromto->{$_});
08ad6bd5	253	print "cp $_ $fromto->{$_}\n";
	254	next unless /\.pm$/;
	255	autosplit($fromto->{$_},$autodir);
	256	}
	257	umask $umask unless $Is_VMS;
4b6d56d3	258	}
4b6d56d3	259
f1387719	260	package ExtUtils::Install::Warn;
	261
	262	sub new { bless {}, shift }
	263
	264	sub add {
	265	my($self,$file,$targetfile) = @_;
	266	push @{$self->{$file}}, $targetfile;
	267	}
	268
	269	sub DESTROY {
	270	my $self = shift;
	271	my($file,$i,$plural);
	272	foreach $file (sort keys %$self) {
	273	$plural = @{$self->{$file}} > 1 ? "s" : "";
	274	print "## Differing version$plural of $file found. You might like to\n";
	275	for (0..$#{$self->{$file}}) {
	276	print "rm ", $self->{$file}[$_], "\n";
	277	$i++;
	278	}
	279	}
	280	$plural = $i>1 ? "all those files" : "this file";
	281	print "## Running 'make install UNINST=1' will unlink $plural for you.\n";
	282	}
	283
4b6d56d3	284	1;
	285
	286	__END__
	287
	288	=head1 NAME
	289
	290	ExtUtils::Install - install files from here to there
	291
	292	=head1 SYNOPSIS
	293
	294	B<use ExtUtils::Install;>
	295
	296	B<install($hashref,$verbose,$nonono);>
	297
	298	B<uninstall($packlistfile,$verbose,$nonono);>
	299
08ad6bd5	300	B<pm_to_blib($hashref);>
08ad6bd5	301
4b6d56d3	302	=head1 DESCRIPTION
4b6d56d3	303
08ad6bd5	304	Both install() and uninstall() are specific to the way
4b6d56d3	305	ExtUtils::MakeMaker handles the installation and deinstallation of
	306	perl modules. They are not designed as general purpose tools.
	307
	308	install() takes three arguments. A reference to a hash, a verbose
	309	switch and a don't-really-do-it switch. The hash ref contains a
	310	mapping of directories: each key/value pair is a combination of
	311	directories to be copied. Key is a directory to copy from, value is a
	312	directory to copy to. The whole tree below the "from" directory will
	313	be copied preserving timestamps and permissions.
	314
	315	There are two keys with a special meaning in the hash: "read" and
	316	"write". After the copying is done, install will write the list of
1fef88e7	317	target files to the file named by C<$hashref-E<gt>{write}>. If there is
1fef88e7	318	another file named by C<$hashref-E<gt>{read}>, the contents of this file will
4b6d56d3	319	be merged into the written file. The read and the written file may be
	320	identical, but on AFS it is quite likely, people are installing to a
	321	different directory than the one where the files later appear.
	322
	323	uninstall() takes as first argument a file containing filenames to be
	324	unlinked. The second argument is a verbose switch, the third is a
	325	no-don't-really-do-it-now switch.
	326
08ad6bd5	327	pm_to_blib() takes a hashref as the first argument and copies all keys
	328	of the hash to the corresponding values efficiently. Filenames with
	329	the extension pm are autosplit. Second argument is the autosplit
	330	directory.
4b6d56d3	331
08ad6bd5	332	=cut