package Shell;
-use 5.005_64;
-our($capture_stderr $VERSION);
+use 5.006_001;
+use strict;
+use warnings;
+use File::Spec::Functions;
-$VERSION = '0.2';
+our($capture_stderr, $raw, $VERSION, $AUTOLOAD);
+
+$VERSION = '0.6';
+
+sub new { bless \my $foo, shift }
+sub DESTROY { }
sub import {
my $self = shift;
my @EXPORT;
if (@_) {
@EXPORT = @_;
- }
- else {
+ } else {
@EXPORT = 'AUTOLOAD';
}
- foreach $sym (@EXPORT) {
+ foreach my $sym (@EXPORT) {
+ no strict 'refs';
*{"${callpack}::$sym"} = \&{"Shell::$sym"};
}
-};
+}
-AUTOLOAD {
+sub AUTOLOAD {
+ shift if ref $_[0] && $_[0]->isa( 'Shell' );
my $cmd = $AUTOLOAD;
$cmd =~ s/^.*:://;
+ my $null = File::Spec::Functions::devnull();
+ $Shell::capture_stderr ||= 0;
eval <<"*END*";
sub $AUTOLOAD {
+ shift if ref \$_[0] && \$_[0]->isa( 'Shell' );
if (\@_ < 1) {
- \$Shell::capture_stderr ? `$cmd 2>&1` : `$cmd`;
- }
- elsif ('$^O' eq 'os2') {
+ \$Shell::capture_stderr == 1 ? `$cmd 2>&1` :
+ \$Shell::capture_stderr == -1 ? `$cmd 2>$null` :
+ `$cmd`;
+ } elsif ('$^O' eq 'os2') {
local(\*SAVEOUT, \*READ, \*WRITE);
open SAVEOUT, '>&STDOUT' or die;
close READ;
waitpid \$pid, 0;
\@ret;
- }
- else {
+ } else {
local(\$/) = undef;
my \$ret = <READ>;
close READ;
waitpid \$pid, 0;
\$ret;
}
- }
- else {
+ } else {
my \$a;
my \@arr = \@_;
- if ('$^O' eq 'MSWin32') {
+ unless( \$Shell::raw ){
+ if ('$^O' eq 'MSWin32') {
# XXX this special-casing should not be needed
# if we do quoting right on Windows. :-(
#
for (\@arr) {
s/"/\\\\"/g;
s/\\\\\\\\"/\\\\\\\\"""/g;
- \$_ = qq["\$_"] if /\s/;
+ \$_ = qq["\$_"] if /\\s/;
}
- }
- else {
+ } else {
for (\@arr) {
s/(['\\\\])/\\\\\$1/g;
- \$_ = "'\$_'";
- }
+ \$_ = \$_;
+ }
+ }
}
- push \@arr, '2>&1' if \$Shell::capture_stderr;
+ push \@arr, '2>&1' if \$Shell::capture_stderr == 1;
+ push \@arr, '2>$null' if \$Shell::capture_stderr == -1;
open(SUBPROC, join(' ', '$cmd', \@arr, '|'))
or die "Can't exec $cmd: \$!\\n";
if (wantarray) {
my \@ret = <SUBPROC>;
close SUBPROC; # XXX Oughta use a destructor.
\@ret;
- }
- else {
+ } else {
local(\$/) = undef;
my \$ret = <SUBPROC>;
close SUBPROC;
}
1;
+
__END__
=head1 NAME
=head1 SYNOPSIS
-See below.
+ use Shell qw(cat ps cp);
+ $passwd = cat('</etc/passwd');
+ @pslines = ps('-ww'),
+ cp("/etc/passwd", "/tmp/passwd");
+
+ # object oriented
+ my $sh = Shell->new;
+ print $sh->ls('-l');
=head1 DESCRIPTION
+=head2 Caveats
+
+This package is included as a show case, illustrating a few Perl features.
+It shouldn't be used for production programs. Although it does provide a
+simple interface for obtaining the standard output of arbitrary commands,
+there may be better ways of achieving what you need.
+
+Running shell commands while obtaining standard output can be done with the
+C<qx/STRING/> operator, or by calling C<open> with a filename expression that
+ends with C<|>, giving you the option to process one line at a time.
+If you don't need to process standard output at all, you might use C<system>
+(in preference of doing a print with the collected standard output).
+
+Since Shell.pm and all of the aforementioned techniques use your system's
+shell to call some local command, none of them is portable across different
+systems. Note, however, that there are several built in functions and
+library packages providing portable implementations of functions operating
+on files, such as: C<glob>, C<link> and C<unlink>, C<mkdir> and C<rmdir>,
+C<rename>, C<File::Compare>, C<File::Copy>, C<File::Find> etc.
+
+Using Shell.pm while importing C<foo> creates a subroutine C<foo> in the
+namespace of the importing package. Calling C<foo> with arguments C<arg1>,
+C<arg2>,... results in a shell command C<foo arg1 arg2...>, where the
+function name and the arguments are joined with a blank. (See the subsection
+on Escaping magic characters.) Since the result is essentially a command
+line to be passed to the shell, your notion of arguments to the Perl
+function is not necessarily identical to what the shell treats as a
+command line token, to be passed as an individual argument to the program.
+Furthermore, note that this implies that C<foo> is callable by file name
+only, which frequently depends on the setting of the program's environment.
+
+Creating a Shell object gives you the opportunity to call any command
+in the usual OO notation without requiring you to announce it in the
+C<use Shell> statement. Don't assume any additional semantics being
+associated with a Shell object: in no way is it similar to a shell
+process with its environment or current working directory or any
+other setting.
+
+=head2 Escaping Magic Characters
+
+It is, in general, impossible to take care of quoting the shell's
+magic characters. For some obscure reason, however, Shell.pm quotes
+apostrophes (C<'>) and backslashes (C<\>) on UNIX, and spaces and
+quotes (C<">) on Windows.
+
+=head2 Configuration
+
+If you set $Shell::capture_stderr to true, the module will attempt to
+capture the standard error output of the process as well. This is
+done by adding C<2E<gt>&1> to the command line, so don't try this on
+a system not supporting this redirection.
+
+If you set $Shell::raw to true no quoting whatsoever is done.
+
+=head1 BUGS
+
+Quoting should be off by default.
+
+It isn't possible to call shell built in commands, but it can be
+done by using a workaround, e.g. shell( '-c', 'set' ).
+
+Capturing standard error does not work on some systems (e.g. VMS).
+
+=head1 AUTHOR
+
Date: Thu, 22 Sep 94 16:18:16 -0700
Message-Id: <9409222318.AA17072@scalpel.netlabs.com>
To: perl5-porters@isu.edu
sub ps;
print ps -ww;
- cp("/etc/passwd", "/tmp/passwd");
+ cp("/etc/passwd", "/etc/passwd.orig");
That's maybe too gonzo. It actually exports an AUTOLOAD to the current
package (and uncovered a bug in Beta 3, by the way). Maybe the usual
use Shell qw(echo cat ps cp);
-Larry
-
-
-If you set $Shell::capture_stderr to 1, the module will attempt to
-capture the STDERR of the process as well.
-
-The module now should work on Win32.
-
- Jenda
+Larry Wall
-=head1 AUTHOR
+Changes by Jenda@Krynicky.cz and Dave Cottle <d.cottle@csc.canterbury.ac.nz>.
-Larry Wall
+Changes for OO syntax and bug fixes by Casey West <casey@geeknest.com>.
-Changes by Jenda@Krynicky.cz and Dave Cottle <d.cottle@csc.canterbury.ac.nz>
+C<$Shell::raw> and pod rewrite by Wolfgang Laun.
=cut
https://perl5.git.perl.org / perl5.git / blobdiff