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1 | # FindBin.pm |
2 | # | |
3 | # Copyright (c) 1995 Graham Barr & Nick Ing-Simmons. All rights reserved. | |
4 | # This program is free software; you can redistribute it and/or modify it | |
5 | # under the same terms as Perl itself. | |
6 | ||
7 | =head1 NAME | |
8 | ||
9 | FindBin - Locate directory of original perl script | |
10 | ||
11 | =head1 SYNOPSIS | |
12 | ||
13 | use FindBin; | |
14 | use lib "$FindBin::Bin/../lib"; | |
15 | ||
16 | or | |
17 | ||
18 | use FindBin qw($Bin); | |
19 | use lib "$Bin/../lib"; | |
20 | ||
21 | =head1 DESCRIPTION | |
22 | ||
23 | Locates the full path to the script bin directory to allow the use | |
24 | of paths relative to the bin directory. | |
25 | ||
26 | This allows a user to setup a directory tree for some software with | |
27 | directories C<< <root>/bin >> and C<< <root>/lib >>, and then the above | |
28 | example will allow the use of modules in the lib directory without knowing | |
29 | where the software tree is installed. | |
30 | ||
31 | If perl is invoked using the B<-e> option or the perl script is read from | |
32 | C<STDIN> then FindBin sets both C<$Bin> and C<$RealBin> to the current | |
33 | directory. | |
34 | ||
35 | =head1 EXPORTABLE VARIABLES | |
36 | ||
37 | $Bin - path to bin directory from where script was invoked | |
38 | $Script - basename of script from which perl was invoked | |
39 | $RealBin - $Bin with all links resolved | |
40 | $RealScript - $Script with all links resolved | |
41 | ||
42 | =head1 KNOWN ISSUES | |
43 | ||
44 | If there are two modules using C<FindBin> from different directories | |
45 | under the same interpreter, this won't work. Since C<FindBin> uses a | |
46 | C<BEGIN> block, it'll be executed only once, and only the first caller | |
47 | will get it right. This is a problem under mod_perl and other persistent | |
48 | Perl environments, where you shouldn't use this module. Which also means | |
49 | that you should avoid using C<FindBin> in modules that you plan to put | |
50 | on CPAN. To make sure that C<FindBin> will work is to call the C<again> | |
51 | function: | |
52 | ||
53 | use FindBin; | |
54 | FindBin::again(); # or FindBin->again; | |
55 | ||
56 | In former versions of FindBin there was no C<again> function. The | |
57 | workaround was to force the C<BEGIN> block to be executed again: | |
58 | ||
59 | delete $INC{'FindBin.pm'}; | |
60 | require FindBin; | |
61 | ||
62 | =head1 KNOWN BUGS | |
63 | ||
64 | If perl is invoked as | |
65 | ||
66 | perl filename | |
67 | ||
68 | and I<filename> does not have executable rights and a program called | |
69 | I<filename> exists in the users C<$ENV{PATH}> which satisfies both B<-x> | |
70 | and B<-T> then FindBin assumes that it was invoked via the | |
71 | C<$ENV{PATH}>. | |
72 | ||
73 | Workaround is to invoke perl as | |
74 | ||
75 | perl ./filename | |
76 | ||
77 | =head1 AUTHORS | |
78 | ||
79 | FindBin is supported as part of the core perl distribution. Please send bug | |
80 | reports to E<lt>F<perlbug@perl.org>E<gt> using the perlbug program | |
81 | included with perl. | |
82 | ||
83 | Graham Barr E<lt>F<gbarr@pobox.com>E<gt> | |
84 | Nick Ing-Simmons E<lt>F<nik@tiuk.ti.com>E<gt> | |
85 | ||
86 | =head1 COPYRIGHT | |
87 | ||
88 | Copyright (c) 1995 Graham Barr & Nick Ing-Simmons. All rights reserved. | |
89 | This program is free software; you can redistribute it and/or modify it | |
90 | under the same terms as Perl itself. | |
91 | ||
92 | =cut | |
93 | ||
94 | package FindBin; | |
95 | use Carp; | |
96 | require 5.000; | |
97 | require Exporter; | |
98 | use Cwd qw(getcwd cwd abs_path); | |
99 | use Config; | |
100 | use File::Basename; | |
101 | use File::Spec; | |
102 | ||
103 | @EXPORT_OK = qw($Bin $Script $RealBin $RealScript $Dir $RealDir); | |
104 | %EXPORT_TAGS = (ALL => [qw($Bin $Script $RealBin $RealScript $Dir $RealDir)]); | |
105 | @ISA = qw(Exporter); | |
106 | ||
107 | $VERSION = "1.47"; | |
108 | ||
109 | sub cwd2 { | |
110 | my $cwd = getcwd(); | |
111 | # getcwd might fail if it hasn't access to the current directory. | |
112 | # try harder. | |
113 | defined $cwd or $cwd = cwd(); | |
114 | $cwd; | |
115 | } | |
116 | ||
117 | sub init | |
118 | { | |
119 | *Dir = \$Bin; | |
120 | *RealDir = \$RealBin; | |
121 | ||
122 | if($0 eq '-e' || $0 eq '-') | |
123 | { | |
124 | # perl invoked with -e or script is on C<STDIN> | |
125 | $Script = $RealScript = $0; | |
126 | $Bin = $RealBin = cwd2(); | |
127 | } | |
128 | else | |
129 | { | |
130 | my $script = $0; | |
131 | ||
132 | if ($^O eq 'VMS') | |
133 | { | |
134 | ($Bin,$Script) = VMS::Filespec::rmsexpand($0) =~ /(.*\])(.*)/s; | |
135 | ($RealBin,$RealScript) = ($Bin,$Script); | |
136 | } | |
137 | else | |
138 | { | |
139 | my $dosish = ($^O eq 'MSWin32' or $^O eq 'os2'); | |
140 | unless(($script =~ m#/# || ($dosish && $script =~ m#\\#)) | |
141 | && -f $script) | |
142 | { | |
143 | my $dir; | |
144 | foreach $dir (File::Spec->path) | |
145 | { | |
146 | my $scr = File::Spec->catfile($dir, $script); | |
147 | if(-r $scr && (!$dosish || -x _)) | |
148 | { | |
149 | $script = $scr; | |
150 | ||
151 | if (-f $0) | |
152 | { | |
153 | # $script has been found via PATH but perl could have | |
154 | # been invoked as 'perl file'. Do a dumb check to see | |
155 | # if $script is a perl program, if not then $script = $0 | |
156 | # | |
157 | # well we actually only check that it is an ASCII file | |
158 | # we know its executable so it is probably a script | |
159 | # of some sort. | |
160 | ||
161 | $script = $0 unless(-T $script); | |
162 | } | |
163 | last; | |
164 | } | |
165 | } | |
166 | } | |
167 | ||
168 | croak("Cannot find current script '$0'") unless(-f $script); | |
169 | ||
170 | # Ensure $script contains the complete path in case we C<chdir> | |
171 | ||
172 | $script = File::Spec->catfile(cwd2(), $script) | |
173 | unless File::Spec->file_name_is_absolute($script); | |
174 | ||
175 | ($Script,$Bin) = fileparse($script); | |
176 | ||
177 | # Resolve $script if it is a link | |
178 | while(1) | |
179 | { | |
180 | my $linktext = readlink($script); | |
181 | ||
182 | ($RealScript,$RealBin) = fileparse($script); | |
183 | last unless defined $linktext; | |
184 | ||
185 | $script = (File::Spec->file_name_is_absolute($linktext)) | |
186 | ? $linktext | |
187 | : File::Spec->catfile($RealBin, $linktext); | |
188 | } | |
189 | ||
190 | # Get absolute paths to directories | |
191 | if ($Bin) { | |
192 | my $BinOld = $Bin; | |
193 | $Bin = abs_path($Bin); | |
194 | defined $Bin or $Bin = File::Spec->canonpath($BinOld); | |
195 | } | |
196 | $RealBin = abs_path($RealBin) if($RealBin); | |
197 | } | |
198 | } | |
199 | } | |
200 | ||
201 | BEGIN { init } | |
202 | ||
203 | *again = \&init; | |
204 | ||
205 | 1; # Keep require happy |