VMS::Filespec - convert between VMS and Unix file specification syntax
This package provides routines to simplify conversion between
VMS and Unix syntax when processing file specifications. This is useful when porting scripts designed to run under either
OS, and also allows you to take advantage of conveniences provided by either syntax (
ability to easily concatenate Unix-style specifications). In addition, it
provides an additional file test routine,
candelete, which determines whether you have delete access to a file.
If you're running under
VMS, the routines in this package are special, in that
they're automatically made available to any Perl script, whether you're
running miniperl or the full perl. The
require VMS::Filespec; import VMS::Filespec ...
statement can be used to import the function names into the current
package, but they're always available if you use the fully qualified name,
whether or not you've mentioned the .pm file in your script. If you're running under another
OS and have installed this package, it behaves like a normal Perl extension (in fact, you're using Perl substitutes to emulate the necessary
VMS system calls).
Each of these routines accepts a file specification in either
VMS or Unix syntax, and returns the converted file
specification, or undef
if an error occurs. The conversions are, for the most part, simply string manipulations; the routines do not check the details of syntax (e.g. that only legal characters are used). There is one exception: when running under
VMS, conversions from
VMS syntax use the
$PARSE service to expand specifications, so illegal syntax, or a relative directory specification which extends above the tope of the current directory path (e.g [---.foo] when in dev:[dir.sub]) will cause errors. In general, any legal file specification will be converted properly, but garbage input tends to produce garbage output.
Each of these routines is prototyped as taking a single scalar argument, so
you can use them as unary operators in complex expressions (as long as you
don't use the
& form of subroutine call, which bypasses prototype checking).
The routines provided are:
services to expand the input specification to its fully qualified form,
except that a null type or version is not added unless it was present in
either the original file specification or the default specification passed
rmsexpand. (If the file does not exist, the input specification is expanded as much
as possible.) If an error occurs, returns undef and sets
Converts a file specification to VMS syntax.
Converts a file specification to Unix syntax.
Converts a directory specification to a path - that is, a string you can prepend to a file name to form a valid file specification. If the input file specification uses VMS syntax, the returned path does, too; likewise for Unix syntax (Unix paths are guaranteed to end with '/'). Note that this routine will insist that the input be a legal directory file specification; the file type and version, if specified, must be .DIR;1. For compatibility with Unix usage, the type and version may also be omitted.
Converts a directory specification to the file specification of the
directory file - that is, a string you can pass to functions like
stat or rmdir to manipulate the directory file. If the input directory specification uses
VMS syntax, the returned file specification does, too; likewise for Unix syntax. As with
pathify, the input file specification must have a type and version of .DIR;1, or the type and version must be omitted.
pathify, but insures the returned path uses
pathify, but insures the returned path uses Unix syntax.
Determines whether you have delete access to a file. If you do,
returns true. If you don't, or its argument isn't a legal file
FALSE. Unlike other file tests, the argument to
candelete must be a file name (not a FileHandle), and, since it's an
XSUB, it's a list operator, so you need to be careful
about parentheses. Both of these restrictions may be removed in the future
if the functionality of
candelete becomes part of the Perl core.
This document was last revised 22-Feb-1996, for Perl 5.002.
If rather than formatting bugs, you encounter substantive content errors in these documents, such as mistakes in the explanations or code, please use the perlbug utility included with the Perl distribution.