[OpenSPARC-T2-DV] / tools / perl-5.8.0 / lib / 5.8.0 / IPC / Open3.pm

package IPC::Open3;

use strict;
no strict 'refs'; # because users pass me bareword filehandles
our ($VERSION, @ISA, @EXPORT);

require Exporter;

use Carp;
use Symbol qw(gensym qualify);

$VERSION	= 1.0104;
@ISA		= qw(Exporter);
@EXPORT		= qw(open3);

=head1 NAME

IPC::Open3, open3 - open a process for reading, writing, and error handling

=head1 SYNOPSIS

    $pid = open3(\*WTRFH, \*RDRFH, \*ERRFH,
		    'some cmd and args', 'optarg', ...);

    my($wtr, $rdr, $err);
    $pid = open3($wtr, $rdr, $err,
		    'some cmd and args', 'optarg', ...);

=head1 DESCRIPTION

Extremely similar to open2(), open3() spawns the given $cmd and
connects RDRFH for reading, WTRFH for writing, and ERRFH for errors.  If
ERRFH is false, or the same file descriptor as RDRFH, then STDOUT and 
STDERR of the child are on the same filehandle.  The WTRFH will have
autoflush turned on.

If WTRFH begins with C<< <& >>, then WTRFH will be closed in the parent, and
the child will read from it directly.  If RDRFH or ERRFH begins with
C<< >& >>, then the child will send output directly to that filehandle.
In both cases, there will be a dup(2) instead of a pipe(2) made.

If either reader or writer is the null string, this will be replaced
by an autogenerated filehandle.  If so, you must pass a valid lvalue
in the parameter slot so it can be overwritten in the caller, or 
an exception will be raised.

The filehandles may also be integers, in which case they are understood
as file descriptors.

open3() returns the process ID of the child process.  It doesn't return on
failure: it just raises an exception matching C</^open3:/>.  However,
C<exec> failures in the child are not detected.  You'll have to 
trap SIGPIPE yourself.

open3() does not wait for and reap the child process after it exits.  
Except for short programs where it's acceptable to let the operating system
take care of this, you need to do this yourself.  This is normally as 
simple as calling C<waitpid $pid, 0> when you're done with the process.
Failing to do this can result in an accumulation of defunct or "zombie"
processes.  See L<perlfunc/waitpid> for more information.

If you try to read from the child's stdout writer and their stderr
writer, you'll have problems with blocking, which means you'll want
to use select() or the IO::Select, which means you'd best use
sysread() instead of readline() for normal stuff.

This is very dangerous, as you may block forever.  It assumes it's
going to talk to something like B<bc>, both writing to it and reading
from it.  This is presumably safe because you "know" that commands
like B<bc> will read a line at a time and output a line at a time.
Programs like B<sort> that read their entire input stream first,
however, are quite apt to cause deadlock.

The big problem with this approach is that if you don't have control
over source code being run in the child process, you can't control
what it does with pipe buffering.  Thus you can't just open a pipe to
C<cat -v> and continually read and write a line from it.

=head1 WARNING

The order of arguments differs from that of open2().

=cut

# &open3: Marc Horowitz <marc@mit.edu>
# derived mostly from &open2 by tom christiansen, <tchrist@convex.com>
# fixed for 5.001 by Ulrich Kunitz <kunitz@mai-koeln.com>
# ported to Win32 by Ron Schmidt, Merrill Lynch almost ended my career
# fixed for autovivving FHs, tchrist again
# allow fd numbers to be used, by Frank Tobin
#
# $Id: open3.pl,v 1.1 1993/11/23 06:26:15 marc Exp $
#
# usage: $pid = open3('wtr', 'rdr', 'err' 'some cmd and args', 'optarg', ...);
#
# spawn the given $cmd and connect rdr for
# reading, wtr for writing, and err for errors.
# if err is '', or the same as rdr, then stdout and
# stderr of the child are on the same fh.  returns pid
# of child (or dies on failure).


# if wtr begins with '<&', then wtr will be closed in the parent, and
# the child will read from it directly.  if rdr or err begins with
# '>&', then the child will send output directly to that fd.  In both
# cases, there will be a dup() instead of a pipe() made.


# WARNING: this is dangerous, as you may block forever
# unless you are very careful.
#
# $wtr is left unbuffered.
#
# abort program if
#   rdr or wtr are null
#   a system call fails

our $Me = 'open3 (bug)';	# you should never see this, it's always localized

# Fatal.pm needs to be fixed WRT prototypes.

sub xfork {
    my $pid = fork;
    defined $pid or croak "$Me: fork failed: $!";
    return $pid;
}

sub xpipe {
    pipe $_[0], $_[1] or croak "$Me: pipe($_[0], $_[1]) failed: $!";
}

# I tried using a * prototype character for the filehandle but it still
# disallows a bearword while compiling under strict subs.

sub xopen {
    open $_[0], $_[1] or croak "$Me: open($_[0], $_[1]) failed: $!";
}

sub xclose {
    close $_[0] or croak "$Me: close($_[0]) failed: $!";
}

sub fh_is_fd {
    return $_[0] =~ /\A=?(\d+)\z/;
}

sub xfileno {
    return $1 if $_[0] =~ /\A=?(\d+)\z/;  # deal with fh just being an fd
    return fileno $_[0];
}

my $do_spawn = $^O eq 'os2' || $^O eq 'MSWin32';

sub _open3 {
    local $Me = shift;
    my($package, $dad_wtr, $dad_rdr, $dad_err, @cmd) = @_;
    my($dup_wtr, $dup_rdr, $dup_err, $kidpid);

    # simulate autovivification of filehandles because
    # it's too ugly to use @_ throughout to make perl do it for us
    # tchrist 5-Mar-00

    unless (eval  {
	$dad_wtr = $_[1] = gensym unless defined $dad_wtr && length $dad_wtr;
	$dad_rdr = $_[2] = gensym unless defined $dad_rdr && length $dad_rdr;
	1; }) 
    {
	# must strip crud for croak to add back, or looks ugly
	$@ =~ s/(?<=value attempted) at .*//s;
	croak "$Me: $@";
    } 

    $dad_err ||= $dad_rdr;

    $dup_wtr = ($dad_wtr =~ s/^[<>]&//);
    $dup_rdr = ($dad_rdr =~ s/^[<>]&//);
    $dup_err = ($dad_err =~ s/^[<>]&//);

    # force unqualified filehandles into caller's package
    $dad_wtr = qualify $dad_wtr, $package unless fh_is_fd($dad_wtr);
    $dad_rdr = qualify $dad_rdr, $package unless fh_is_fd($dad_rdr);
    $dad_err = qualify $dad_err, $package unless fh_is_fd($dad_err);

    my $kid_rdr = gensym;
    my $kid_wtr = gensym;
    my $kid_err = gensym;

    xpipe $kid_rdr, $dad_wtr if !$dup_wtr;
    xpipe $dad_rdr, $kid_wtr if !$dup_rdr;
    xpipe $dad_err, $kid_err if !$dup_err && $dad_err ne $dad_rdr;

    $kidpid = $do_spawn ? -1 : xfork;
    if ($kidpid == 0) {		# Kid
	# If she wants to dup the kid's stderr onto her stdout I need to
	# save a copy of her stdout before I put something else there.
	if ($dad_rdr ne $dad_err && $dup_err
		&& xfileno($dad_err) == fileno(STDOUT)) {
	    my $tmp = gensym;
	    xopen($tmp, ">&$dad_err");
	    $dad_err = $tmp;
	}

	if ($dup_wtr) {
	    xopen \*STDIN,  "<&$dad_wtr" if fileno(STDIN) != xfileno($dad_wtr);
	} else {
	    xclose $dad_wtr;
	    xopen \*STDIN,  "<&=" . fileno $kid_rdr;
	}
	if ($dup_rdr) {
	    xopen \*STDOUT, ">&$dad_rdr" if fileno(STDOUT) != xfileno($dad_rdr);
	} else {
	    xclose $dad_rdr;
	    xopen \*STDOUT, ">&=" . fileno $kid_wtr;
	}
	if ($dad_rdr ne $dad_err) {
	    if ($dup_err) {
		# I have to use a fileno here because in this one case
		# I'm doing a dup but the filehandle might be a reference
		# (from the special case above).
		xopen \*STDERR, ">&" . xfileno($dad_err)
		    if fileno(STDERR) != xfileno($dad_err);
	    } else {
		xclose $dad_err;
		xopen \*STDERR, ">&=" . fileno $kid_err;
	    }
	} else {
	    xopen \*STDERR, ">&STDOUT" if fileno(STDERR) != fileno(STDOUT);
	}
	local($")=(" ");
	exec @cmd # XXX: wrong process to croak from
	    or croak "$Me: exec of @cmd failed";
    } elsif ($do_spawn) {
	# All the bookkeeping of coincidence between handles is
	# handled in spawn_with_handles.

	my @close;
	if ($dup_wtr) {
	  $kid_rdr = \*{$dad_wtr};
	  push @close, $kid_rdr;
	} else {
	  push @close, \*{$dad_wtr}, $kid_rdr;
	}
	if ($dup_rdr) {
	  $kid_wtr = \*{$dad_rdr};
	  push @close, $kid_wtr;
	} else {
	  push @close, \*{$dad_rdr}, $kid_wtr;
	}
	if ($dad_rdr ne $dad_err) {
	    if ($dup_err) {
	      $kid_err = \*{$dad_err};
	      push @close, $kid_err;
	    } else {
	      push @close, \*{$dad_err}, $kid_err;
	    }
	} else {
	  $kid_err = $kid_wtr;
	}
	require IO::Pipe;
	$kidpid = eval {
	    spawn_with_handles( [ { mode => 'r',
				    open_as => $kid_rdr,
				    handle => \*STDIN },
				  { mode => 'w',
				    open_as => $kid_wtr,
				    handle => \*STDOUT },
				  { mode => 'w',
				    open_as => $kid_err,
				    handle => \*STDERR },
				], \@close, @cmd);
	};
	die "$Me: $@" if $@;
    }

    xclose $kid_rdr if !$dup_wtr;
    xclose $kid_wtr if !$dup_rdr;
    xclose $kid_err if !$dup_err && $dad_rdr ne $dad_err;
    # If the write handle is a dup give it away entirely, close my copy
    # of it.
    xclose $dad_wtr if $dup_wtr;

    select((select($dad_wtr), $| = 1)[0]); # unbuffer pipe
    $kidpid;
}

sub open3 {
    if (@_ < 4) {
	local $" = ', ';
	croak "open3(@_): not enough arguments";
    }
    return _open3 'open3', scalar caller, @_
}

sub spawn_with_handles {
    my $fds = shift;		# Fields: handle, mode, open_as
    my $close_in_child = shift;
    my ($fd, $pid, @saved_fh, $saved, %saved, @errs);
    require Fcntl;

    foreach $fd (@$fds) {
	$fd->{tmp_copy} = IO::Handle->new_from_fd($fd->{handle}, $fd->{mode});
	$saved{fileno $fd->{handle}} = $fd->{tmp_copy};
    }
    foreach $fd (@$fds) {
	bless $fd->{handle}, 'IO::Handle'
	    unless eval { $fd->{handle}->isa('IO::Handle') } ;
	# If some of handles to redirect-to coincide with handles to
	# redirect, we need to use saved variants:
	$fd->{handle}->fdopen($saved{fileno $fd->{open_as}} || $fd->{open_as},
			      $fd->{mode});
    }
    unless ($^O eq 'MSWin32') {
	# Stderr may be redirected below, so we save the err text:
	foreach $fd (@$close_in_child) {
	    fcntl($fd, Fcntl::F_SETFD(), 1) or push @errs, "fcntl $fd: $!"
		unless $saved{fileno $fd}; # Do not close what we redirect!
	}
    }

    unless (@errs) {
	$pid = eval { system 1, @_ }; # 1 == P_NOWAIT
	push @errs, "IO::Pipe: Can't spawn-NOWAIT: $!" if !$pid || $pid < 0;
    }

    foreach $fd (@$fds) {
	$fd->{handle}->fdopen($fd->{tmp_copy}, $fd->{mode});
	$fd->{tmp_copy}->close or croak "Can't close: $!";
    }
    croak join "\n", @errs if @errs;
    return $pid;
}

1; # so require is happy
Commit	Line	Data
86530b38 AT	1	package IPC::Open3;
	2
	3	use strict;
	4	no strict 'refs'; # because users pass me bareword filehandles
	5	our ($VERSION, @ISA, @EXPORT);
	6
	7	require Exporter;
	8
	9	use Carp;
	10	use Symbol qw(gensym qualify);
	11
	12	$VERSION = 1.0104;
	13	@ISA = qw(Exporter);
	14	@EXPORT = qw(open3);
	15
	16	=head1 NAME
	17
	18	IPC::Open3, open3 - open a process for reading, writing, and error handling
	19
	20	=head1 SYNOPSIS
	21
	22	$pid = open3(\WTRFH, \RDRFH, \*ERRFH,
	23	'some cmd and args', 'optarg', ...);
	24
	25	my($wtr, $rdr, $err);
	26	$pid = open3($wtr, $rdr, $err,
	27	'some cmd and args', 'optarg', ...);
	28
	29	=head1 DESCRIPTION
	30
	31	Extremely similar to open2(), open3() spawns the given $cmd and
	32	connects RDRFH for reading, WTRFH for writing, and ERRFH for errors. If
	33	ERRFH is false, or the same file descriptor as RDRFH, then STDOUT and
	34	STDERR of the child are on the same filehandle. The WTRFH will have
	35	autoflush turned on.
	36
	37	If WTRFH begins with C<< <& >>, then WTRFH will be closed in the parent, and
	38	the child will read from it directly. If RDRFH or ERRFH begins with
	39	C<< >& >>, then the child will send output directly to that filehandle.
	40	In both cases, there will be a dup(2) instead of a pipe(2) made.
	41
	42	If either reader or writer is the null string, this will be replaced
	43	by an autogenerated filehandle. If so, you must pass a valid lvalue
	44	in the parameter slot so it can be overwritten in the caller, or
	45	an exception will be raised.
	46
	47	The filehandles may also be integers, in which case they are understood
	48	as file descriptors.
	49
	50	open3() returns the process ID of the child process. It doesn't return on
	51	failure: it just raises an exception matching C</^open3:/>. However,
	52	C<exec> failures in the child are not detected. You'll have to
	53	trap SIGPIPE yourself.
	54
	55	open3() does not wait for and reap the child process after it exits.
	56	Except for short programs where it's acceptable to let the operating system
	57	take care of this, you need to do this yourself. This is normally as
	58	simple as calling C<waitpid $pid, 0> when you're done with the process.
	59	Failing to do this can result in an accumulation of defunct or "zombie"
	60	processes. See L<perlfunc/waitpid> for more information.
	61
	62	If you try to read from the child's stdout writer and their stderr
	63	writer, you'll have problems with blocking, which means you'll want
	64	to use select() or the IO::Select, which means you'd best use
65	sysread() instead of readline() for normal stuff.
66
67	This is very dangerous, as you may block forever. It assumes it's
68	going to talk to something like B<bc>, both writing to it and reading
69	from it. This is presumably safe because you "know" that commands
70	like B<bc> will read a line at a time and output a line at a time.
71	Programs like B<sort> that read their entire input stream first,
72	however, are quite apt to cause deadlock.
73
74	The big problem with this approach is that if you don't have control
75	over source code being run in the child process, you can't control
76	what it does with pipe buffering. Thus you can't just open a pipe to
77	C<cat -v> and continually read and write a line from it.
78
79	=head1 WARNING
80
81	The order of arguments differs from that of open2().
82
83	=cut
84
85	# &open3: Marc Horowitz <marc@mit.edu>
86	# derived mostly from &open2 by tom christiansen, <tchrist@convex.com>
87	# fixed for 5.001 by Ulrich Kunitz <kunitz@mai-koeln.com>
88	# ported to Win32 by Ron Schmidt, Merrill Lynch almost ended my career
89	# fixed for autovivving FHs, tchrist again
90	# allow fd numbers to be used, by Frank Tobin
91	#
92	# $Id: open3.pl,v 1.1 1993/11/23 06:26:15 marc Exp $
93	#
94	# usage: $pid = open3('wtr', 'rdr', 'err' 'some cmd and args', 'optarg', ...);
95	#
96	# spawn the given $cmd and connect rdr for
97	# reading, wtr for writing, and err for errors.
98	# if err is '', or the same as rdr, then stdout and
99	# stderr of the child are on the same fh. returns pid
100	# of child (or dies on failure).
101
102
103	# if wtr begins with '<&', then wtr will be closed in the parent, and
104	# the child will read from it directly. if rdr or err begins with
105	# '>&', then the child will send output directly to that fd. In both
106	# cases, there will be a dup() instead of a pipe() made.
107
108
109	# WARNING: this is dangerous, as you may block forever
110	# unless you are very careful.
111	#
112	# $wtr is left unbuffered.
113	#
114	# abort program if
115	# rdr or wtr are null
116	# a system call fails
117
118	our $Me = 'open3 (bug)'; # you should never see this, it's always localized
119
120	# Fatal.pm needs to be fixed WRT prototypes.
121
122	sub xfork {
123	my $pid = fork;
124	defined $pid or croak "$Me: fork failed: $!";
125	return $pid;
126	}
127
128	sub xpipe {
129	pipe $_[0], $_[1] or croak "$Me: pipe($_[0], $_[1]) failed: $!";
130	}
131
132	# I tried using a * prototype character for the filehandle but it still
133	# disallows a bearword while compiling under strict subs.
134
135	sub xopen {
136	open $_[0], $_[1] or croak "$Me: open($_[0], $_[1]) failed: $!";
137	}
138
139	sub xclose {
140	close $_[0] or croak "$Me: close($_[0]) failed: $!";
141	}
142
143	sub fh_is_fd {
144	return $_[0] =~ /\A=?(\d+)\z/;
145	}
146
147	sub xfileno {
148	return $1 if $_[0] =~ /\A=?(\d+)\z/; # deal with fh just being an fd
149	return fileno $_[0];
150	}
151
152	my $do_spawn = $^O eq 'os2' \|\| $^O eq 'MSWin32';
153
154	sub _open3 {
155	local $Me = shift;
156	my($package, $dad_wtr, $dad_rdr, $dad_err, @cmd) = @_;
157	my($dup_wtr, $dup_rdr, $dup_err, $kidpid);
158
159	# simulate autovivification of filehandles because
160	# it's too ugly to use @_ throughout to make perl do it for us
161	# tchrist 5-Mar-00
162
163	unless (eval {
164	$dad_wtr = $_[1] = gensym unless defined $dad_wtr && length $dad_wtr;
165	$dad_rdr = $_[2] = gensym unless defined $dad_rdr && length $dad_rdr;
166	1; })
167	{
168	# must strip crud for croak to add back, or looks ugly
169	$@ =~ s/(?<=value attempted) at .*//s;
170	croak "$Me: $@";
171	}
172
173	$dad_err \|\|= $dad_rdr;
174
175	$dup_wtr = ($dad_wtr =~ s/^[<>]&//);
176	$dup_rdr = ($dad_rdr =~ s/^[<>]&//);
177	$dup_err = ($dad_err =~ s/^[<>]&//);
178
179	# force unqualified filehandles into caller's package
180	$dad_wtr = qualify $dad_wtr, $package unless fh_is_fd($dad_wtr);
181	$dad_rdr = qualify $dad_rdr, $package unless fh_is_fd($dad_rdr);
182	$dad_err = qualify $dad_err, $package unless fh_is_fd($dad_err);
183
184	my $kid_rdr = gensym;
185	my $kid_wtr = gensym;
186	my $kid_err = gensym;
187
188	xpipe $kid_rdr, $dad_wtr if !$dup_wtr;
189	xpipe $dad_rdr, $kid_wtr if !$dup_rdr;
190	xpipe $dad_err, $kid_err if !$dup_err && $dad_err ne $dad_rdr;
191
192	$kidpid = $do_spawn ? -1 : xfork;
193	if ($kidpid == 0) { # Kid
194	# If she wants to dup the kid's stderr onto her stdout I need to
195	# save a copy of her stdout before I put something else there.
196	if ($dad_rdr ne $dad_err && $dup_err
197	&& xfileno($dad_err) == fileno(STDOUT)) {
198	my $tmp = gensym;
199	xopen($tmp, ">&$dad_err");
200	$dad_err = $tmp;
201	}
202
203	if ($dup_wtr) {
204	xopen \*STDIN, "<&$dad_wtr" if fileno(STDIN) != xfileno($dad_wtr);
205	} else {
206	xclose $dad_wtr;
207	xopen \*STDIN, "<&=" . fileno $kid_rdr;
208	}
209	if ($dup_rdr) {
210	xopen \*STDOUT, ">&$dad_rdr" if fileno(STDOUT) != xfileno($dad_rdr);
211	} else {
212	xclose $dad_rdr;
213	xopen \*STDOUT, ">&=" . fileno $kid_wtr;
214	}
215	if ($dad_rdr ne $dad_err) {
216	if ($dup_err) {
217	# I have to use a fileno here because in this one case
218	# I'm doing a dup but the filehandle might be a reference
219	# (from the special case above).
220	xopen \*STDERR, ">&" . xfileno($dad_err)
221	if fileno(STDERR) != xfileno($dad_err);
222	} else {
223	xclose $dad_err;
224	xopen \*STDERR, ">&=" . fileno $kid_err;
225	}
226	} else {
227	xopen \*STDERR, ">&STDOUT" if fileno(STDERR) != fileno(STDOUT);
228	}
229	local($")=(" ");
230	exec @cmd # XXX: wrong process to croak from
231	or croak "$Me: exec of @cmd failed";
232	} elsif ($do_spawn) {
233	# All the bookkeeping of coincidence between handles is
234	# handled in spawn_with_handles.
235
236	my @close;
237	if ($dup_wtr) {
238	$kid_rdr = \*{$dad_wtr};
239	push @close, $kid_rdr;
240	} else {
241	push @close, \*{$dad_wtr}, $kid_rdr;
242	}
243	if ($dup_rdr) {
244	$kid_wtr = \*{$dad_rdr};
245	push @close, $kid_wtr;
246	} else {
247	push @close, \*{$dad_rdr}, $kid_wtr;
248	}
249	if ($dad_rdr ne $dad_err) {
250	if ($dup_err) {
251	$kid_err = \*{$dad_err};
252	push @close, $kid_err;
253	} else {
254	push @close, \*{$dad_err}, $kid_err;
255	}
256	} else {
257	$kid_err = $kid_wtr;
258	}
259	require IO::Pipe;
260	$kidpid = eval {
261	spawn_with_handles( [ { mode => 'r',
262	open_as => $kid_rdr,
263	handle => \*STDIN },
264	{ mode => 'w',
265	open_as => $kid_wtr,
266	handle => \*STDOUT },
267	{ mode => 'w',
268	open_as => $kid_err,
269	handle => \*STDERR },
270	], \@close, @cmd);
271	};
272	die "$Me: $@" if $@;
273	}
274
275	xclose $kid_rdr if !$dup_wtr;
276	xclose $kid_wtr if !$dup_rdr;
277	xclose $kid_err if !$dup_err && $dad_rdr ne $dad_err;
278	# If the write handle is a dup give it away entirely, close my copy
279	# of it.
280	xclose $dad_wtr if $dup_wtr;
281
282	select((select($dad_wtr), $\| = 1)[0]); # unbuffer pipe
283	$kidpid;
284	}
285
286	sub open3 {
287	if (@_ < 4) {
288	local $" = ', ';
289	croak "open3(@_): not enough arguments";
290	}
291	return _open3 'open3', scalar caller, @_
292	}
293
294	sub spawn_with_handles {
295	my $fds = shift; # Fields: handle, mode, open_as
296	my $close_in_child = shift;
297	my ($fd, $pid, @saved_fh, $saved, %saved, @errs);
298	require Fcntl;
299
300	foreach $fd (@$fds) {
301	$fd->{tmp_copy} = IO::Handle->new_from_fd($fd->{handle}, $fd->{mode});
302	$saved{fileno $fd->{handle}} = $fd->{tmp_copy};
303	}
304	foreach $fd (@$fds) {
305	bless $fd->{handle}, 'IO::Handle'
306	unless eval { $fd->{handle}->isa('IO::Handle') } ;
307	# If some of handles to redirect-to coincide with handles to
308	# redirect, we need to use saved variants:
309	$fd->{handle}->fdopen($saved{fileno $fd->{open_as}} \|\| $fd->{open_as},
310	$fd->{mode});
311	}
312	unless ($^O eq 'MSWin32') {
313	# Stderr may be redirected below, so we save the err text:
314	foreach $fd (@$close_in_child) {
315	fcntl($fd, Fcntl::F_SETFD(), 1) or push @errs, "fcntl $fd: $!"
316	unless $saved{fileno $fd}; # Do not close what we redirect!
317	}
318	}
319
320	unless (@errs) {
321	$pid = eval { system 1, @_ }; # 1 == P_NOWAIT
322	push @errs, "IO::Pipe: Can't spawn-NOWAIT: $!" if !$pid \|\| $pid < 0;
323	}
324
325	foreach $fd (@$fds) {
326	$fd->{handle}->fdopen($fd->{tmp_copy}, $fd->{mode});
327	$fd->{tmp_copy}->close or croak "Can't close: $!";
328	}
329	croak join "\n", @errs if @errs;
330	return $pid;
331	}
332
333	1; # so require is happy