1 package File::Basename;
5 Basename - parse file specifications
7 fileparse - split a pathname into pieces
9 basename - extract just the filename from a path
11 dirname - extract just the directory from a path
17 ($name,$path,$suffix) = fileparse($fullname,@suffixlist)
18 fileparse_set_fstype($os_string);
19 $basename = basename($fullname,@suffixlist);
20 $dirname = dirname($fullname);
22 ($name,$path,$suffix) = fileparse("lib/File/Basename.pm","\.pm");
23 fileparse_set_fstype("VMS");
24 $basename = basename("lib/File/Basename.pm",".pm");
25 $dirname = dirname("lib/File/Basename.pm");
29 These routines allow you to parse file specifications into useful
30 pieces using the syntax of different operating systems.
34 =item fileparse_set_fstype
36 You select the syntax via the routine fileparse_set_fstype().
37 If the argument passed to it contains one of the substrings
38 "VMS", "MSDOS", or "MacOS", the file specification syntax of that
39 operating system is used in future calls to fileparse(),
40 basename(), and dirname(). If it contains none of these
41 substrings, UNIX syntax is used. This pattern matching is
42 case-insensitive. If you've selected VMS syntax, and the file
43 specification you pass to one of these routines contains a "/",
44 they assume you are using UNIX emulation and apply the UNIX syntax
45 rules instead, for that function call only.
47 If you haven't called fileparse_set_fstype(), the syntax is chosen
48 by examining the builtin variable C<$^O> according to these rules.
52 The fileparse() routine divides a file specification into three
53 parts: a leading B<path>, a file B<name>, and a B<suffix>. The
54 B<path> contains everything up to and including the last directory
55 separator in the input file specification. The remainder of the input
56 file specification is then divided into B<name> and B<suffix> based on
57 the optional patterns you specify in C<@suffixlist>. Each element of
58 this list is interpreted as a regular expression, and is matched
59 against the end of B<name>. If this succeeds, the matching portion of
60 B<name> is removed and prepended to B<suffix>. By proper use of
61 C<@suffixlist>, you can remove file types or versions for examination.
63 You are guaranteed that if you concatenate B<path>, B<name>, and
64 B<suffix> together in that order, the result will be identical to the
65 input file specification.
71 Using UNIX file syntax:
73 ($base,$path,$type) = fileparse('/virgil/aeneid/draft.book7',
79 $path eq '/virgil/aeneid',
82 Similarly, using VMS syntax:
84 ($name,$dir,$type) = fileparse('Doc_Root:[Help]Rhetoric.Rnh',
90 $dir eq 'Doc_Root:[Help]'
95 The basename() routine returns the first element of the list produced
96 by calling fileparse() with the same arguments. It is provided for
97 compatibility with the UNIX shell command basename(1).
101 The dirname() routine returns the directory portion of the input file
102 specification. When using VMS or MacOS syntax, this is identical to the
103 second element of the list produced by calling fileparse() with the same
104 input file specification. When using UNIX or MSDOS syntax, the return
105 value conforms to the behavior of the UNIX shell command dirname(1). This
106 is usually the same as the behavior of fileparse(), but differs in some
107 cases. For example, for the input file specification F<lib/>, fileparse()
108 considers the directory name to be F<lib/>, while dirname() considers the
109 directory name to be F<.>).
116 @EXPORT = qw(fileparse fileparse_set_fstype basename dirname);
118 # fileparse_set_fstype() - specify OS-based rules used in future
119 # calls to routines in this package
121 # Currently recognized values: VMS, MSDOS, MacOS
122 # Any other name uses Unix-style rules
124 sub fileparse_set_fstype {
125 my($old) = $Fileparse_fstype;
126 $Fileparse_fstype = $_[0] if $_[0];
130 # fileparse() - parse file specification
133 # ($filename,$prefix,$tail) = &basename_pat($filespec,@excludelist);
134 # where $filespec is the file specification to be parsed, and
135 # @excludelist is a list of patterns which should be removed
136 # from the end of $filename.
137 # $filename is the part of $filespec after $prefix (i.e. the
138 # name of the file). The elements of @excludelist
139 # are compared to $filename, and if an
140 # $prefix is the path portion $filespec, up to and including
141 # the end of the last directory name
142 # $tail any characters removed from $filename because they
143 # matched an element of @excludelist.
145 # fileparse() first removes the directory specification from $filespec,
146 # according to the syntax of the OS (code is provided below to handle
147 # VMS, Unix, MSDOS and MacOS; you can pick the one you want using
148 # fileparse_set_fstype(), or you can accept the default, which is
149 # based on the information in the builtin variable $^O). It then compares
150 # each element of @excludelist to $filename, and if that element is a
151 # suffix of $filename, it is removed from $filename and prepended to
152 # $tail. By specifying the elements of @excludelist in the right order,
153 # you can 'nibble back' $filename to extract the portion of interest
156 # For example, on a system running Unix,
157 # ($base,$path,$type) = fileparse('/virgil/aeneid/draft.book7',
159 # would yield $base == 'draft',
160 # $path == '/virgil/aeneid/' (note trailing slash)
162 # Similarly, on a system running VMS,
163 # ($name,$dir,$type) = fileparse('Doc_Root:[Help]Rhetoric.Rnh','\..*');
164 # would yield $name == 'Rhetoric';
165 # $dir == 'Doc_Root:[Help]', and
168 # Version 2.2 13-Oct-1994 Charles Bailey bailey@genetics.upenn.edu
172 my($fullname,@suffices) = @_;
173 my($fstype) = $Fileparse_fstype;
174 my($dirpath,$tail,$suffix);
176 if ($fstype =~ /^VMS/i) {
177 if ($fullname =~ m#/#) { $fstype = '' } # We're doing Unix emulation
179 ($dirpath,$basename) = ($fullname =~ /(.*[:>\]])?(.*)/);
180 $dirpath = $ENV{'DEFAULT'} unless $dirpath;
183 if ($fstype =~ /^MSDOS/i) {
184 ($dirpath,$basename) = ($fullname =~ /(.*\\)?(.*)/);
185 $dirpath = '.\\' unless $dirpath;
187 elsif ($fstype =~ /^MAC/i) {
188 ($dirpath,$basename) = ($fullname =~ /(.*:)?(.*)/);
190 elsif ($fstype !~ /^VMS/i) { # default to Unix
191 ($dirpath,$basename) = ($fullname =~ m#(.*/)?(.*)#);
192 $dirpath = './' unless $dirpath;
197 foreach $suffix (@suffices) {
198 if ($basename =~ /($suffix)$/) {
205 wantarray ? ($basename,$dirpath,$tail) : $basename;
210 # basename() - returns first element of list returned by fileparse()
214 (fileparse($name, map("\Q$_\E",@_)))[0];
218 # dirname() - returns device and directory portion of file specification
219 # Behavior matches that of Unix dirname(1) exactly for Unix and MSDOS
220 # filespecs except for names ending with a separator, e.g., "/xx/yy/".
221 # This differs from the second element of the list returned
222 # by fileparse() in that the trailing '/' (Unix) or '\' (MSDOS) (and
223 # the last directory name if the filespec ends in a '/' or '\'), is lost.
226 my($basename,$dirname) = fileparse($_[0]);
227 my($fstype) = $Fileparse_fstype;
229 if ($fstype =~ /VMS/i) {
230 if ($_[0] =~ m#/#) { $fstype = '' }
231 else { return $dirname }
233 if ($fstype =~ /MacOS/i) { return $dirname }
234 elsif ($fstype =~ /MSDOS/i) {
235 if ( $dirname =~ /:\\$/) { return $dirname }
237 $dirname =~ s:[^\\]+$:: unless $basename;
238 $dirname = '.' unless $dirname;
241 if ( $dirname eq '/') { return $dirname }
243 $dirname =~ s:[^/]+$:: unless $basename;
244 $dirname = '.' unless $dirname;
250 $Fileparse_fstype = $^O;