Commit | Line | Data |
---|---|---|
a0d0e21e | 1 | package Shell; |
3b825e41 | 2 | use 5.006_001; |
8d5b6de5 CT |
3 | use strict; |
4 | use warnings; | |
d0b4fbd9 DM |
5 | use File::Spec::Functions; |
6 | ||
96412ebc | 7 | our($capture_stderr, $raw, $VERSION, $AUTOLOAD); |
a0d0e21e | 8 | |
96412ebc | 9 | $VERSION = '0.6'; |
8d5b6de5 | 10 | |
605870ff | 11 | sub new { bless \my $foo, shift } |
8d5b6de5 | 12 | sub DESTROY { } |
4633a7c4 | 13 | |
a0d0e21e LW |
14 | sub import { |
15 | my $self = shift; | |
16 | my ($callpack, $callfile, $callline) = caller; | |
17 | my @EXPORT; | |
18 | if (@_) { | |
19 | @EXPORT = @_; | |
8d5b6de5 | 20 | } else { |
a0d0e21e LW |
21 | @EXPORT = 'AUTOLOAD'; |
22 | } | |
8d5b6de5 CT |
23 | foreach my $sym (@EXPORT) { |
24 | no strict 'refs'; | |
a0d0e21e LW |
25 | *{"${callpack}::$sym"} = \&{"Shell::$sym"}; |
26 | } | |
8d5b6de5 | 27 | } |
a0d0e21e | 28 | |
8d5b6de5 CT |
29 | sub AUTOLOAD { |
30 | shift if ref $_[0] && $_[0]->isa( 'Shell' ); | |
a0d0e21e LW |
31 | my $cmd = $AUTOLOAD; |
32 | $cmd =~ s/^.*:://; | |
d0b4fbd9 | 33 | my $null = File::Spec::Functions::devnull(); |
c4a2e7a5 | 34 | $Shell::capture_stderr ||= 0; |
253924a2 GS |
35 | eval <<"*END*"; |
36 | sub $AUTOLOAD { | |
51947a20 | 37 | shift if ref \$_[0] && \$_[0]->isa( 'Shell' ); |
4633a7c4 | 38 | if (\@_ < 1) { |
c4a2e7a5 | 39 | \$Shell::capture_stderr == 1 ? `$cmd 2>&1` : |
d0b4fbd9 | 40 | \$Shell::capture_stderr == -1 ? `$cmd 2>$null` : |
c4a2e7a5 | 41 | `$cmd`; |
8d5b6de5 | 42 | } elsif ('$^O' eq 'os2') { |
4633a7c4 LW |
43 | local(\*SAVEOUT, \*READ, \*WRITE); |
44 | ||
45 | open SAVEOUT, '>&STDOUT' or die; | |
46 | pipe READ, WRITE or die; | |
47 | open STDOUT, '>&WRITE' or die; | |
48 | close WRITE; | |
49 | ||
253924a2 GS |
50 | my \$pid = system(1, '$cmd', \@_); |
51 | die "Can't execute $cmd: \$!\\n" if \$pid < 0; | |
4633a7c4 LW |
52 | |
53 | open STDOUT, '>&SAVEOUT' or die; | |
54 | close SAVEOUT; | |
55 | ||
56 | if (wantarray) { | |
57 | my \@ret = <READ>; | |
58 | close READ; | |
59 | waitpid \$pid, 0; | |
60 | \@ret; | |
8d5b6de5 | 61 | } else { |
4633a7c4 LW |
62 | local(\$/) = undef; |
63 | my \$ret = <READ>; | |
64 | close READ; | |
65 | waitpid \$pid, 0; | |
66 | \$ret; | |
67 | } | |
8d5b6de5 | 68 | } else { |
253924a2 GS |
69 | my \$a; |
70 | my \@arr = \@_; | |
96412ebc WL |
71 | unless( \$Shell::raw ){ |
72 | if ('$^O' eq 'MSWin32') { | |
253924a2 GS |
73 | # XXX this special-casing should not be needed |
74 | # if we do quoting right on Windows. :-( | |
75 | # | |
76 | # First, escape all quotes. Cover the case where we | |
77 | # want to pass along a quote preceded by a backslash | |
78 | # (i.e., C<"param \\""" end">). | |
79 | # Ugly, yup? You know, windoze. | |
80 | # Enclose in quotes only the parameters that need it: | |
81 | # try this: c:\> dir "/w" | |
82 | # and this: c:\> dir /w | |
83 | for (\@arr) { | |
84 | s/"/\\\\"/g; | |
85 | s/\\\\\\\\"/\\\\\\\\"""/g; | |
6570f784 | 86 | \$_ = qq["\$_"] if /\\s/; |
253924a2 | 87 | } |
96412ebc | 88 | } else { |
253924a2 GS |
89 | for (\@arr) { |
90 | s/(['\\\\])/\\\\\$1/g; | |
8d5b6de5 | 91 | \$_ = \$_; |
96412ebc WL |
92 | } |
93 | } | |
253924a2 | 94 | } |
c4a2e7a5 | 95 | push \@arr, '2>&1' if \$Shell::capture_stderr == 1; |
d0b4fbd9 | 96 | push \@arr, '2>$null' if \$Shell::capture_stderr == -1; |
253924a2 GS |
97 | open(SUBPROC, join(' ', '$cmd', \@arr, '|')) |
98 | or die "Can't exec $cmd: \$!\\n"; | |
a0d0e21e LW |
99 | if (wantarray) { |
100 | my \@ret = <SUBPROC>; | |
101 | close SUBPROC; # XXX Oughta use a destructor. | |
102 | \@ret; | |
8d5b6de5 | 103 | } else { |
a0d0e21e LW |
104 | local(\$/) = undef; |
105 | my \$ret = <SUBPROC>; | |
106 | close SUBPROC; | |
107 | \$ret; | |
108 | } | |
109 | } | |
110 | } | |
253924a2 GS |
111 | *END* |
112 | ||
113 | die "$@\n" if $@; | |
a0d0e21e LW |
114 | goto &$AUTOLOAD; |
115 | } | |
116 | ||
117 | 1; | |
8d5b6de5 | 118 | |
a5f75d66 AD |
119 | __END__ |
120 | ||
121 | =head1 NAME | |
122 | ||
123 | Shell - run shell commands transparently within perl | |
124 | ||
125 | =head1 SYNOPSIS | |
126 | ||
96412ebc WL |
127 | use Shell qw(cat ps cp); |
128 | $passwd = cat('</etc/passwd'); | |
129 | @pslines = ps('-ww'), | |
130 | cp("/etc/passwd", "/tmp/passwd"); | |
131 | ||
132 | # object oriented | |
133 | my $sh = Shell->new; | |
134 | print $sh->ls('-l'); | |
a5f75d66 AD |
135 | |
136 | =head1 DESCRIPTION | |
137 | ||
96412ebc WL |
138 | =head2 Caveats |
139 | ||
140 | This package is included as a show case, illustrating a few Perl features. | |
141 | It shouldn't be used for production programs. Although it does provide a | |
142 | simple interface for obtaining the standard output of arbitrary commands, | |
143 | there may be better ways of achieving what you need. | |
144 | ||
145 | Running shell commands while obtaining standard output can be done with the | |
146 | C<qx/STRING/> operator, or by calling C<open> with a filename expression that | |
147 | ends with C<|>, giving you the option to process one line at a time. | |
148 | If you don't need to process standard output at all, you might use C<system> | |
149 | (in preference of doing a print with the collected standard output). | |
150 | ||
151 | Since Shell.pm and all of the aforementioned techniques use your system's | |
152 | shell to call some local command, none of them is portable across different | |
153 | systems. Note, however, that there are several built in functions and | |
154 | library packages providing portable implementations of functions operating | |
155 | on files, such as: C<glob>, C<link> and C<unlink>, C<mkdir> and C<rmdir>, | |
156 | C<rename>, C<File::Compare>, C<File::Copy>, C<File::Find> etc. | |
157 | ||
158 | Using Shell.pm while importing C<foo> creates a subroutine C<foo> in the | |
159 | namespace of the importing package. Calling C<foo> with arguments C<arg1>, | |
160 | C<arg2>,... results in a shell command C<foo arg1 arg2...>, where the | |
161 | function name and the arguments are joined with a blank. (See the subsection | |
162 | on Escaping magic characters.) Since the result is essentially a command | |
163 | line to be passed to the shell, your notion of arguments to the Perl | |
164 | function is not necessarily identical to what the shell treats as a | |
165 | command line token, to be passed as an individual argument to the program. | |
166 | Furthermore, note that this implies that C<foo> is callable by file name | |
167 | only, which frequently depends on the setting of the program's environment. | |
168 | ||
169 | Creating a Shell object gives you the opportunity to call any command | |
170 | in the usual OO notation without requiring you to announce it in the | |
171 | C<use Shell> statement. Don't assume any additional semantics being | |
172 | associated with a Shell object: in no way is it similar to a shell | |
173 | process with its environment or current working directory or any | |
174 | other setting. | |
175 | ||
176 | =head2 Escaping Magic Characters | |
177 | ||
178 | It is, in general, impossible to take care of quoting the shell's | |
179 | magic characters. For some obscure reason, however, Shell.pm quotes | |
180 | apostrophes (C<'>) and backslashes (C<\>) on UNIX, and spaces and | |
181 | quotes (C<">) on Windows. | |
182 | ||
183 | =head2 Configuration | |
184 | ||
185 | If you set $Shell::capture_stderr to true, the module will attempt to | |
186 | capture the standard error output of the process as well. This is | |
187 | done by adding C<2E<gt>&1> to the command line, so don't try this on | |
188 | a system not supporting this redirection. | |
189 | ||
190 | If you set $Shell::raw to true no quoting whatsoever is done. | |
191 | ||
192 | =head1 BUGS | |
193 | ||
194 | Quoting should be off by default. | |
195 | ||
196 | It isn't possible to call shell built in commands, but it can be | |
197 | done by using a workaround, e.g. shell( '-c', 'set' ). | |
198 | ||
199 | Capturing standard error does not work on some systems (e.g. VMS). | |
200 | ||
201 | =head1 AUTHOR | |
202 | ||
a5f75d66 AD |
203 | Date: Thu, 22 Sep 94 16:18:16 -0700 |
204 | Message-Id: <9409222318.AA17072@scalpel.netlabs.com> | |
205 | To: perl5-porters@isu.edu | |
206 | From: Larry Wall <lwall@scalpel.netlabs.com> | |
207 | Subject: a new module I just wrote | |
208 | ||
209 | Here's one that'll whack your mind a little out. | |
210 | ||
211 | #!/usr/bin/perl | |
212 | ||
213 | use Shell; | |
214 | ||
215 | $foo = echo("howdy", "<funny>", "world"); | |
216 | print $foo; | |
217 | ||
218 | $passwd = cat("</etc/passwd"); | |
219 | print $passwd; | |
220 | ||
221 | sub ps; | |
222 | print ps -ww; | |
223 | ||
2359510d | 224 | cp("/etc/passwd", "/etc/passwd.orig"); |
a5f75d66 AD |
225 | |
226 | That's maybe too gonzo. It actually exports an AUTOLOAD to the current | |
227 | package (and uncovered a bug in Beta 3, by the way). Maybe the usual | |
228 | usage should be | |
229 | ||
230 | use Shell qw(echo cat ps cp); | |
231 | ||
a5f75d66 AD |
232 | Larry Wall |
233 | ||
96412ebc WL |
234 | Changes by Jenda@Krynicky.cz and Dave Cottle <d.cottle@csc.canterbury.ac.nz>. |
235 | ||
236 | Changes for OO syntax and bug fixes by Casey West <casey@geeknest.com>. | |
253924a2 | 237 | |
96412ebc | 238 | C<$Shell::raw> and pod rewrite by Wolfgang Laun. |
8d5b6de5 | 239 | |
a5f75d66 | 240 | =cut |