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Updated: Wednesday, July 27, 2022
 
 

File::Glob (3)

Name

File::Glob - Perl extension for BSD glob routine

Synopsis

use File::Glob ':bsd_glob';

@list = bsd_glob('*.[ch]');
$homedir = bsd_glob('~gnat', GLOB_TILDE | GLOB_ERR);

if (GLOB_ERROR) {
# an error occurred reading $homedir
}

## override the core glob (CORE::glob() does this automatically
## by default anyway, since v5.6.0)
use File::Glob ':globally';
my @sources = <*.{c,h,y}>;

## override the core glob, forcing case sensitivity
use File::Glob qw(:globally :case);
my @sources = <*.{c,h,y}>;

## override the core glob forcing case insensitivity
use File::Glob qw(:globally :nocase);
my @sources = <*.{c,h,y}>;

## glob on all files in home directory
use File::Glob ':globally';
my @sources = <~gnat/*>;

Description

Perl Programmers Reference Guide                                 File::Glob(3)



NAME
       File::Glob - Perl extension for BSD glob routine

SYNOPSIS
         use File::Glob ':bsd_glob';

         @list = bsd_glob('*.[ch]');
         $homedir = bsd_glob('~gnat', GLOB_TILDE | GLOB_ERR);

         if (GLOB_ERROR) {
           # an error occurred reading $homedir
         }

         ## override the core glob (CORE::glob() does this automatically
         ## by default anyway, since v5.6.0)
         use File::Glob ':globally';
         my @sources = <*.{c,h,y}>;

         ## override the core glob, forcing case sensitivity
         use File::Glob qw(:globally :case);
         my @sources = <*.{c,h,y}>;

         ## override the core glob forcing case insensitivity
         use File::Glob qw(:globally :nocase);
         my @sources = <*.{c,h,y}>;

         ## glob on all files in home directory
         use File::Glob ':globally';
         my @sources = <~gnat/*>;

DESCRIPTION
       The glob angle-bracket operator "<>" is a pathname generator that
       implements the rules for file name pattern matching used by Unix-like
       shells such as the Bourne shell or C shell.

       File::Glob::bsd_glob() implements the FreeBSD glob(3) routine, which is
       a superset of the POSIX glob() (described in IEEE Std 1003.2
       "POSIX.2").  bsd_glob() takes a mandatory "pattern" argument, and an
       optional "flags" argument, and returns a list of filenames matching the
       pattern, with interpretation of the pattern modified by the "flags"
       variable.

       Since v5.6.0, Perl's CORE::glob() is implemented in terms of
       bsd_glob().  Note that they don't share the same
       prototype--CORE::glob() only accepts a single argument.  Due to
       historical reasons, CORE::glob() will also split its argument on
       whitespace, treating it as multiple patterns, whereas bsd_glob()
       considers them as one pattern.  But see ":bsd_glob" under "EXPORTS",
       below.

   META CHARACTERS
         \       Quote the next metacharacter
         []      Character class
         {}      Multiple pattern
         *       Match any string of characters
         ?       Match any single character
         ~       User name home directory

       The metanotation "a{b,c,d}e" is a shorthand for "abe ace ade".  Left to
       right order is preserved, with results of matches being sorted
       separately at a low level to preserve this order.  As a special case
       "{", "}", and "{}" are passed undisturbed.

   EXPORTS
       See also the "POSIX FLAGS" below, which can be exported individually.

       ":bsd_glob"

       The ":bsd_glob" export tag exports bsd_glob() and the constants listed
       below.  It also overrides glob() in the calling package with one that
       behaves like bsd_glob() with regard to spaces (the space is treated as
       part of a file name), but supports iteration in scalar context; i.e.,
       it preserves the core function's feature of returning the next item
       each time it is called.

       ":glob"

       The ":glob" tag, now discouraged, is the old version of ":bsd_glob".
       It exports the same constants and functions, but its glob() override
       does not support iteration; it returns the last file name in scalar
       context.  That means this will loop forever:

           use File::Glob ':glob';
           while (my $file = <* copy.txt>) {
               ...
           }

       "bsd_glob"

       This function, which is included in the two export tags listed above,
       takes one or two arguments.  The first is the glob pattern.  The
       second, if given, is a set of flags ORed together.  The available flags
       and the default set of flags are listed below under "POSIX FLAGS".

       Remember that to use the named constants for flags you must import
       them, for example with ":bsd_glob" described above.  If not imported,
       and "use strict" is not in effect, then the constants will be treated
       as bareword strings, which won't do what you what.

       ":nocase" and ":case"

       These two export tags globally modify the default flags that bsd_glob()
       and, except on VMS, Perl's built-in "glob" operator use.  "GLOB_NOCASE"
       is turned on or off, respectively.

       "csh_glob"

       The csh_glob() function can also be exported, but you should not use it
       directly unless you really know what you are doing.  It splits the
       pattern into words and feeds each one to bsd_glob().  Perl's own glob()
       function uses this internally.

   POSIX FLAGS
       If no flags argument is give then "GLOB_CSH" is set, and on VMS and
       Windows systems, "GLOB_NOCASE" too.  Otherwise the flags to use are
       determined solely by the flags argument.  The POSIX defined flags are:

       "GLOB_ERR"
           Force bsd_glob() to return an error when it encounters a directory
           it cannot open or read.  Ordinarily bsd_glob() continues to find
           matches.

       "GLOB_LIMIT"
           Make bsd_glob() return an error (GLOB_NOSPACE) when the pattern
           expands to a size bigger than the system constant "ARG_MAX"
           (usually found in limits.h).  If your system does not define this
           constant, bsd_glob() uses "sysconf(_SC_ARG_MAX)" or
           "_POSIX_ARG_MAX" where available (in that order).  You can inspect
           these values using the standard "POSIX" extension.

       "GLOB_MARK"
           Each pathname that is a directory that matches the pattern has a
           slash appended.

       "GLOB_NOCASE"
           By default, file names are assumed to be case sensitive; this flag
           makes bsd_glob() treat case differences as not significant.

       "GLOB_NOCHECK"
           If the pattern does not match any pathname, then bsd_glob() returns
           a list consisting of only the pattern.  If "GLOB_QUOTE" is set, its
           effect is present in the pattern returned.

       "GLOB_NOSORT"
           By default, the pathnames are sorted in ascending ASCII order; this
           flag prevents that sorting (speeding up bsd_glob()).

       The FreeBSD extensions to the POSIX standard are the following flags:

       "GLOB_BRACE"
           Pre-process the string to expand "{pat,pat,...}" strings like
           csh(1).  The pattern '{}' is left unexpanded for historical reasons
           (and csh(1) does the same thing to ease typing of find(1)
           patterns).

       "GLOB_NOMAGIC"
           Same as "GLOB_NOCHECK" but it only returns the pattern if it does
           not contain any of the special characters "*", "?" or "[".
           "NOMAGIC" is provided to simplify implementing the historic csh(1)
           globbing behaviour and should probably not be used anywhere else.

       "GLOB_QUOTE"
           Use the backslash ('\') character for quoting: every occurrence of
           a backslash followed by a character in the pattern is replaced by
           that character, avoiding any special interpretation of the
           character.  (But see below for exceptions on DOSISH systems).

       "GLOB_TILDE"
           Expand patterns that start with '~' to user name home directories.

       "GLOB_CSH"
           For convenience, "GLOB_CSH" is a synonym for "GLOB_BRACE |
           GLOB_NOMAGIC | GLOB_QUOTE | GLOB_TILDE | GLOB_ALPHASORT".

       The POSIX provided "GLOB_APPEND", "GLOB_DOOFFS", and the FreeBSD
       extensions "GLOB_ALTDIRFUNC", and "GLOB_MAGCHAR" flags have not been
       implemented in the Perl version because they involve more complex
       interaction with the underlying C structures.

       The following flag has been added in the Perl implementation for csh
       compatibility:

       "GLOB_ALPHASORT"
           If "GLOB_NOSORT" is not in effect, sort filenames is alphabetical
           order (case does not matter) rather than in ASCII order.

DIAGNOSTICS
       bsd_glob() returns a list of matching paths, possibly zero length.  If
       an error occurred, &File::Glob::GLOB_ERROR will be non-zero and $! will
       be set.  &File::Glob::GLOB_ERROR is guaranteed to be zero if no error
       occurred, or one of the following values otherwise:

       "GLOB_NOSPACE"
           An attempt to allocate memory failed.

       "GLOB_ABEND"
           The glob was stopped because an error was encountered.

       In the case where bsd_glob() has found some matching paths, but is
       interrupted by an error, it will return a list of filenames and set
       &File::Glob::ERROR.

       Note that bsd_glob() deviates from POSIX and FreeBSD glob(3) behaviour
       by not considering "ENOENT" and "ENOTDIR" as errors - bsd_glob() will
       continue processing despite those errors, unless the "GLOB_ERR" flag is
       set.

       Be aware that all filenames returned from File::Glob are tainted.


ATTRIBUTES
       See attributes(7) for descriptions of the following attributes:


       +---------------+-----------------------+
       |ATTRIBUTE TYPE |   ATTRIBUTE VALUE     |
       +---------------+-----------------------+
       |Availability   | runtime/perl-532      |
       +---------------+-----------------------+
       |Stability      | Pass-through volatile |
       +---------------+-----------------------+

NOTES
       o   If you want to use multiple patterns, e.g. "bsd_glob("a* b*")", you
           should probably throw them in a set as in "bsd_glob("{a*,b*}")".
           This is because the argument to bsd_glob() isn't subjected to
           parsing by the C shell.  Remember that you can use a backslash to
           escape things.

       o   On DOSISH systems, backslash is a valid directory separator
           character.  In this case, use of backslash as a quoting character
           (via GLOB_QUOTE) interferes with the use of backslash as a
           directory separator.  The best (simplest, most portable) solution
           is to use forward slashes for directory separators, and backslashes
           for quoting.  However, this does not match "normal practice" on
           these systems.  As a concession to user expectation, therefore,
           backslashes (under GLOB_QUOTE) only quote the glob metacharacters
           '[', ']', '{', '}', '-', '~', and backslash itself.  All other
           backslashes are passed through unchanged.

       o   Win32 users should use the real slash.  If you really want to use
           backslashes, consider using Sarathy's File::DosGlob, which comes
           with the standard Perl distribution.

           Source code for open source software components in Oracle Solaris
           can be found at
           https://www.oracle.com/downloads/opensource/solaris-source-code-
           downloads.html.

           This software was built from source available at
           https://github.com/oracle/solaris-userland.  The original community
           source was downloaded from
           http://www.cpan.org/src/5.0/perl-5.32.0.tar.gz.

           Further information about this software can be found on the open
           source community website at https://www.perl.org/.

SEE ALSO
       "glob" in perlfunc, glob(3)

AUTHOR
       The Perl interface was written by Nathan Torkington <gnat@frii.com>,
       and is released under the artistic license.  Further modifications were
       made by Greg Bacon <gbacon@cs.uah.edu>, Gurusamy Sarathy
       <gsar@activestate.com>, and Thomas Wegner <wegner_thomas@yahoo.com>.
       The C glob code has the following copyright:

       Copyright (c) 1989, 1993 The Regents of the University of California.
       All rights reserved.

       This code is derived from software contributed to Berkeley by Guido van
       Rossum.

       Redistribution and use in source and binary forms, with or without
       modification, are permitted provided that the following conditions are
       met:

       1.  Redistributions of source code must retain the above copyright
           notice, this list of conditions and the following disclaimer.

       2.  Redistributions in binary form must reproduce the above copyright
           notice, this list of conditions and the following disclaimer in the
           documentation and/or other materials provided with the
           distribution.

       3.  Neither the name of the University nor the names of its
           contributors may be used to endorse or promote products derived
           from this software without specific prior written permission.

       THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS "AS IS" AND
       ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
       IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
       PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS
       BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
       CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
       SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
       BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
       WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
       OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
       ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.




perl v5.32.0                      2020-06-14                     File::Glob(3)