use Carp;
use Symbol 'qualify';
-$VERSION = 1.01;
+$VERSION = 1.0101;
@ISA = qw(Exporter);
@EXPORT = qw(open3);
=head1 SYNOPSIS
- $pid = open3(\*WTRFH, \*RDRFH, \*ERRFH
+ $pid = open3(\*WTRFH, \*RDRFH, \*ERRFH,
'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 '', or the same as RDRFH, then STDOUT and STDERR of the child are
-on the same file handle.
+on the same file handle. The WTRFH will have autoflush turned on.
If WTRFH begins with "E<lt>&", then WTRFH will be closed in the parent, and
the child will read from it directly. If RDRFH or ERRFH begins with
-"E<gt>&", then the child will send output directly to that file handle. In both
-cases, there will be a dup(2) instead of a pipe(2) made.
+"E<gt>&", then the child will send output directly to that file handle.
+In both cases, there will be a dup(2) instead of a pipe(2) made.
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
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 the child process, you can't 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.
close $_[0] or croak "$Me: close($_[0]) failed: $!";
}
+my $do_spawn = $^O eq 'os2';
+
sub _open3 {
local $Me = shift;
my($package, $dad_wtr, $dad_rdr, $dad_err, @cmd) = @_;
xpipe $dad_rdr, $kid_wtr if !$dup_rdr;
xpipe $dad_err, $kid_err if !$dup_err && $dad_err ne $dad_rdr;
- $kidpid = xfork;
- if ($kidpid == 0) {
+ $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 && $dup_err
}
if ($dup_wtr) {
- open(STDIN, "<&$dad_wtr") if (fileno(STDIN) != fileno($dad_wtr));
+ xopen \*STDIN, "<&$dad_wtr" if fileno(STDIN) != fileno($dad_wtr);
} else {
- close($dad_wtr);
- open(STDIN, "<&$kid_rdr");
+ xclose $dad_wtr;
+ xopen \*STDIN, "<&$kid_rdr";
+ xclose $kid_rdr;
}
if ($dup_rdr) {
- open(STDOUT, ">&$dad_rdr") if (fileno(STDOUT) != fileno($dad_rdr));
+ xopen \*STDOUT, ">&$dad_rdr" if fileno(STDOUT) != fileno($dad_rdr);
} else {
- close($dad_rdr);
- open(STDOUT, ">&$kid_wtr");
+ xclose $dad_rdr;
+ xopen \*STDOUT, ">&$kid_wtr";
+ xclose $kid_wtr;
}
if ($dad_rdr ne $dad_err) {
if ($dup_err) {
- open(STDERR, ">&$dad_err")
- if (fileno(STDERR) != fileno($dad_err));
+ xopen \*STDERR, ">&$dad_err"
+ if fileno(STDERR) != fileno($dad_err);
} else {
- close($dad_err);
- open(STDERR, ">&$kid_err");
+ xclose $dad_err;
+ xopen \*STDERR, ">&$kid_err";
+ xclose $kid_err;
}
} else {
- open(STDERR, ">&STDOUT") if (fileno(STDERR) != fileno(STDOUT));
+ xopen \*STDERR, ">&STDOUT" if fileno(STDERR) != fileno(STDOUT);
}
local($")=(" ");
exec @cmd
- or croak "open3: exec of @cmd failed";
+ 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;
}
sub open3 {
+ if (@_ < 4) {
+ local $" = ', ';
+ croak "open3(@_): not enough arguments";
+ }
return _open3 'open3', scalar caller, @_
}
-1; # so require is happy
+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});
+ }
+ # 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
projects / p5sagit/p5-mst-13.2.git / blobdiff