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Re: feeding text to a process, and capturing its output, safely

by duelafn (Vicar)
on Jun 09, 2011 at 16:10 UTC ( #908951=note: print w/replies, xml ) Need Help??

in reply to feeding text to a process, and capturing its output, safely

Converted to a subroutine, make the exec safer, optionally capture STDERR, lexical filehandle:

=head3 safe_pipe safe_pipe [ options, ] command, input my $results = safe_pipe [ 'command', 'arg' ], @input; my @results = safe_pipe [ 'command', 'arg' ], @input; my $results = safe_pipe { capture_err => 1 }, [ 'command', 'arg' ], @ +input; Pipe data to a shell command safely (without touching a command line) +and retrieve the results. Options: =over 4 =item capture_err If true, STDERR will also be captured and included in returned results +. =back =cut sub safe_pipe { my $opt = {}; $opt = shift if 'HASH' eq ref($_[0]); my $command = shift; my ($RESULT, @x); $command = [$command] unless ref $command; if (open $RESULT, "-|") { # original process: receiver (reads $RESUL +T) @x = <$RESULT>; } else { if (open STDIN, "-|") { # child: processor (reads STDIN, writes ST +DOUT) open STDERR, ">&STDOUT" or die "Can't dup STDOUT: $!" if $$opt{c +apture_err}; exec { $$command[0] } @$command; die "Cannot exec @$command: $!"; } else { # grandchild: sender (writes STDOUT) print @_; exit 0; } } wantarray ? @x : join('', @x); }

Good Day,

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