opening a file whose letter case is unknown

[Doron Stein]

Say we have a file named "ABC" , yet A B and C can be upper or lower
case each ( 8 combinations ).

how can one neatly open this file without preprocessing a directory
content ?

i would have wanted something like


open(FILE, "ABC / ignore_case " )

Thanks in advance

Doron.

[Sam Holden]

On Wed, 17 Sep 2003 12:49:19 +0300, Doron Stein <dostein@cisco.com> wrote:

> Say we have a file named "ABC" , yet A B and C can be upper or lower
> case each ( 8 combinations ).
>
> how can one neatly open this file without preprocessing a directory
> content ?
>
> i would have wanted something like
>
>
> open(FILE, "ABC / ignore_case " )

my $file = glob('[Aa][Bb][Cc]');
die "No file matching [Aa][Bb][Cc]" unless defined $file;
open(FILE, $file) or die "Unable to open $file: $!";

Of course that will just read all the filenames in the directory and find
the matches, and is probably inefficient since it will keep searching
after finding a match...

--
Sam Holden

[Kasp]

"Doron Stein" <dostein@cisco.com> wrote in message
news:1063792099.938089@sj-nntpcache-5...

> how can one neatly open this file without preprocessing a directory
> content ?
>
> i would have wanted something like
> open(FILE, "ABC / ignore_case " )

On an OS like Windows, all filenames (upper case or lower case) are treated
alike.
So,
open(FILE, 'ABC.txt');
is same as
open(FILE, 'abc.txt');

I don't know how you can achieve the same for Unix-like systems.
--
"Accept that some days you are the pigeon and some days the statue."
"A pat on the back is only a few inches from a kick in the butt." - Dilbert.

[Doron Stein]

Thanks sam fro the idea ,

and say the file name is a variable , how can i imitate the '[Aa][Bb][Cc]'

Doron.

Sam Holden wrote:

> On Wed, 17 Sep 2003 12:49:19 +0300, Doron Stein <dostein@cisco.com> wrote:
>

>> Say we have a file named "ABC" , yet A B and C can be upper or lower
>>case each ( 8 combinations ).
>>
>>how can one neatly open this file without preprocessing a directory
>>content ?
>>
>>i would have wanted something like
>>
>>
>>open(FILE, "ABC / ignore_case " )

>
>
> my $file = glob('[Aa][Bb][Cc]');
> die "No file matching [Aa][Bb][Cc]" unless defined $file;
> open(FILE, $file) or die "Unable to open $file: $!";
>
> Of course that will just read all the filenames in the directory and find
> the matches, and is probably inefficient since it will keep searching
> after finding a match...
>

[Anno Siegel]

Doron Stein <dostein@cisco.com> wrote in comp.lang.perl.misc:

> Thanks sam fro the idea ,
>
> and say the file name is a variable , how can i imitate the '[Aa][Bb][Cc]'
>
> Doron.

Please don't top-post, it's rude.

(my $pat = $name) =~ s/([[:alpha:]])/[\u$1\l$1]/g;

> Sam Holden wrote:

> > On Wed, 17 Sep 2003 12:49:19 +0300, Doron Stein <dostein@cisco.com> wrote:

[TOFU snipped]

Anno

[Dominik Seelow]

> Say we have a file named "ABC" , yet A B and C can be upper or lower

> case each ( 8 combinations ).
>
> how can one neatly open this file without preprocessing a directory
> content ?
>
> i would have wanted something like
>
>
> open(FILE, "ABC / ignore_case " )
>
> Thanks in advance
>
> Doron.
>

Hello Doron,

as you will have to care for the directory's content anyway, I suggest
to use grep and readdir:

opendir (DIR,'.') || die ($!);
my $filename='voId.txt';
open (FILE, ((grep /$filename/i,readdir DIR)[0])) || die ($!);

This will open the first file found.

HTH,
Dominik

[Abigail]

Doron Stein (dostein@cisco.com) wrote on MMMDCLXIX September MCMXCIII in
<URL:news:1063792099.938089@sj-nntpcache-5>:
@@ Say we have a file named "ABC" , yet A B and C can be upper or lower
@@ case each ( 8 combinations ).
@@
@@ how can one neatly open this file without preprocessing a directory
@@ content ?

What if the directory contains all of "Abc", "aBc" and "abC", which
one do you want to open?

Note that in general, what you want isn't possible. Most file-systems
don't store the file names in an order that depends on the file name.
(And there's not general API for filesystems that do). Even opening
a file means that potentially all of the directory content will be
processed.


Abigail
--
sub f{sprintf'%c%s',$_[0],$_[1]}print f(74,f(117,f(115,f(116,f(32,f(97,
f(110,f(111,f(116,f(104,f(0x65,f(114,f(32,f(80,f(1 01,f(114,f(0x6c,f(32,
f(0x48,f(97,f(99,f(107,f(101,f(114,f(10,q ff)))))))))))))))))))))))))

[Randal L. Schwartz]

>>>>> "Sam" == Sam Holden <sholden@flexal.cs.usyd.edu.au> writes:

Sam> my $file = glob('[Aa][Bb][Cc]');

Don't use glob in a scalar context, as it maintains state. Consider
the output (on a Unix system) of:

for (1..10) {
my $passwd = glob '/etc/passw[d]';
if ($passwd) {
print "found it at $passwd\n";
} else {
print "not found!\n";
}
}

Every other time, it will print "not found", because it didn't find
*another* one.

You want

my ($file) = glob('[Aa][Bb][Cc]');

to get the first one (if any) discarding all others.

print "Just another Perl hacker,"

--
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