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NAME ^

glob - 100% Perl implementation of (t)csh "globbing"

SYNOPSIS ^

On the command-line:

    glob 'eenie{meenie,mynie,moe}*.[ch]'

As a Perl function:

    use FastGlob qw(glob);
    @list = &glob('eenie{meenie,mynie,moe}*.[ch]');

DESCRIPTION ^

The glob command/function implements globbing in perl, rather than forking a csh like Perl's built-in glob() call. This is faster than the built-in glob() call, and more robust (on many platforms, csh chokes on echo * if too many files are in the directory.)

Pattern Matching Syntax for Filename Expansion

The expressions that are passed as arguments to glob must adhere to csh/tcsh pattern-matching syntax for wildcard filename expansion (also known as globbing). Unquoted words containing an asterisk (*), question-mark (?), square-brackets ([...]), or curly-braces ({...}), or beginning with a tilde (~), are expanded into an alphabetically sorted list of filenames, as follows:

*

Match any (zero or more) characters.

?

Match any single character.

[...]

Match any single character in the given character class. The character class is the enclosed list(s) or range(s). A list is a string of characters. A range is two characters separated by a dash (-), and includes all the characters in between the two characters given (inclusive). If a dash (-) is intended to be part of the character class it must be the first character given.

{str1,str2,...}

Expand the given "word-set" to each string (or filename-matching pattern) in the comma-separated list. Unlike the pattern-matching expressions above, the expansion of this construct is not sorted. For instance, {foo,bar} expands to foo bar (not bar foo). As special cases, unmatched { and }, and the "empty set" (the string {}) are treated as ordinary characters instead of pattern-matching meta-characters. A backslash (\) may be used to escape an opening or closing curly brace, or the backslash character itself. Note that word-sets may be nested!

~

The home directory of the invoking user as indicated by the value of the variable $HOME.

~username

The home directory of the user whose login name is 'username', as indicated by the password entry for the named user.

Only the patterns *, ? and [...] imply pattern matching; an error results if no filename matches a pattern that contains them. When a period or "dot" (.) is the first character in a filename or pathname component, it must be matched explicitly. The filename component separator character (e.g., / or slash) must also be matched explicitly.

OPTIONS ^

When invoking glob as a script from the command-line, if the very first argument is -0 (a minus sign followed by the number zero), then a NUL character ("\0") is used to separate the expanded words and/or filenames when printing them to standard output. Otherwise a newline is used as the word/filename output separator.

When invoking glob as a function from the FastGlob module, There are several module-local variables that can be set for alternate environments, they are listed below with their (UNIX-ish) defaults.

        $FastGlob::dirsep = '/';        # directory path separator
        $FastGlob::rootpat = '\A\Z';    # root directory prefix pattern
        $FastGlob::curdir = '.';        # name of current directory in dir
        $FastGlob::parentdir = '..';    # name of parent directory in dir
        $FastGlob::hidedotfiles = 1;    # hide filenames starting with .

So for MS-DOS for example, you could set these to:

        $FastGlob::dirsep = '\\';       # directory path separator
        $FastGlob::rootpat = '[A-Z]:';  # <Drive letter><colon> pattern
        $FastGlob::curdir = '.';        # name of current directory in dir
        $FastGlob::parentdir = '..';    # name of parent directory in dir

        $FastGlob::hidedotfiles = 0;    # hide filenames starting with .

And for MacOS to:

        $FastGlob::dirsep = ':';        # directory path separator
        $FastGlob::rootpat = '\A\Z';    # root directory prefix pattern
        $FastGlob::curdir = '.';        # name of current directory in dir
        $FastGlob::parentdir = '..';    # name of parent directory in dir
        $FastGlob::hidedotfiles = 0;    # hide filenames starting with .

Furthermore, after a call to glob, the variable $FastGlob::matched will indicate the number of valid filenames that were matched, and the array @FastGlob::errors well contain a (possibly empty) list of error messages.

RETURNS ^

When glob is invoked as a script from the command-line, the exit-status returned will be 0 if any files were matched or word-sets were expanded; 1 if no files/word-sets were matched/expanded; and 2 if some other kind of error occurred.

When glob is invoked as a function from the FastGlob module, the return value will be an array of matching filenames and expanded word-sets.

DIAGNOSTICS ^

If no filenames are matched and pattern-matching characters were used (*, ?, or [...]), then an error message of "No Match" is issued. If a user's home directory is specified using tilde-expansion (e.g., ~username) but the corresponding username or their home directory cannot be found, then the error message "Unknown user: username" is issued.

NOTE that when glob is invoked as a script from the command-line then error messages are issued by printing them to standard diagnostic output (STDERR); When glob is invoked as a function from the FastGlob module, then error messages are issued by storing in the @FastGlob::errors array.

COPYRIGHT ^

Copyright (c) 1997-1999 Marc Mengel. All rights reserved.

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

AUTHOR ^

Marc Mengel <mengel@fnal.gov>

REVISIONS ^

Brad Appleton <bradapp@enteract.com> -- v1.2 March 1999

Modified to use qr// (and some other minor speedups), to explode subexpressions in curly braces (a la csh -- rather than using just plain alternation), and made callable as a standalone script.

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