Portable unix du command

[Dan Muey]

Howdy group.

I have a need to get the size of a directory.
I could just execute unix's du command (my $sz = `du -sh /usr`;)
but was wondering if there's a better way to do it that is more portable.
I looked on cpan but didn't see anythign that jumped out at me.

TIA

Dan

[Drieux]

On Tuesday, Nov 18, 2003, at 09:20 US/Pacific, Dan Muey wrote:

> Howdy group.
>
> I have a need to get the size of a directory.
> I could just execute unix's du command (my $sz = `du -sh /usr`;)
> but was wondering if there's a better way to do it that is more
> portable.
> I looked on cpan but didn't see anythign that jumped out at me.
>

a part of the problem is that the 'du' command
is basically implemented differently between the
BSD and SYSV styles of unix. One strategy that
I have adopted when I am looking at a 'common'(HA!)
unix utility that I would like to use, and
in your illustration, the 'flags' to it, that
are problematic, I create a wrapper class.

a quicky way to think about your problem would
be my WhackJob for dealing with my 'favorite'
set of flags to the 'ps' command:

cf
<http://www.wetware.com/drieux/CS/Proj/PID/>

To be honest, I use something like that, but more
cleaned up in a project I have. The trick of
course is getting 'illustrations' from all of the
OS's that you will want to be 'portable' with.

HTH.

ciao
drieux

---

[Dan Muey]

> On Tuesday, Nov 18, 2003, at 09:20 US/Pacific, Dan Muey wrote:
>

> > Howdy group.
> >
> > I have a need to get the size of a directory.
> > I could just execute unix's du command (my $sz = `du -sh

> /usr`;) but

> > was wondering if there's a better way to do it that is more

> portable.

> > I looked on cpan but didn't see anythign that jumped out at me.
> >

>
> a part of the problem is that the 'du' command
> is basically implemented differently between the
> BSD and SYSV styles of unix. One strategy that
> I have adopted when I am looking at a 'common'(HA!)
> unix utility that I would like to use, and
> in your illustration, the 'flags' to it, that
> are problematic, I create a wrapper class.
>
> a quicky way to think about your problem would
> be my WhackJob for dealing with my 'favorite'
> set of flags to the 'ps' command:
>
> cf
> <http://www.wetware.com/drieux/CS/Proj/PID/>
>
> To be honest, I use something like that, but more
> cleaned up in a project I have. The trick of
> course is getting 'illustrations' from all of the
> OS's that you will want to be 'portable' with.
>

Thanks. What I really want to do is avoid system commands completely.
I could always traverse the directory adding the size of each file
together and do that all in Perl with no system commands but I figured
there'd already be a Module or something like this, so I want to do it
that way. Somthign like:

my $sz = $module->size("/home/joemama");
# return sixze of file or of entire directory if specified file is a directory

> HTH.
>
> ciao
> drieux

[John W. Krahn]

Dan Muey wrote:

>
> Thanks. What I really want to do is avoid system commands completely.
> I could always traverse the directory adding the size of each file
> together and do that all in Perl with no system commands but I figured
> there'd already be a Module or something like this, so I want to do it
> that way. Somthign like:

You mean something like (untested):

use File::Find;

my $dir = '/some/dir';
my $size;

find( sub { -f and ( $size += -s _ ) }, $dir );

print "Directory '$dir' contains $size bytes\n";



John
--
use Perl;
program
fulfillment

[Drieux]

On Tuesday, Nov 18, 2003, at 09:35 US/Pacific, Dan Muey wrote:
[..]

>
> Thanks. What I really want to do is avoid system commands completely.
> I could always traverse the directory adding the size of each file
> together and do that all in Perl with no system commands but I figured
> there'd already be a Module or something like this, so I want to do it
> that way. Somthign like:
>
> my $sz = $module->size("/home/joemama");
> # return sixze of file or of entire directory if specified file is a
> directory

I can appreciate the desire, but remember that
"systems applications" - such as 'du' and 'ps'
are there so that folks do not have to know all
of the OS specific underlying 'system calls' that
will flop into 'kernal space'.

The fine folks who are maintaining the Proc::Table
module deliver XS code that gets converted into
the 'c' code that becomes the dynamically loadable
library that is referenced in the "perl module"....

Which is why I opted to take the 'sillier' path
of simply working out which command line arguments
were the 'right ones' for Me based upon the four
or five basic *nix versions that I work with and
then go through the process that way.

If you want to have fun, then you will of course
want to become friends with stat(), cf perldoc -f stat
and/or read the POSIX module, cf perldoc POSIX.

Or download a copy of the open source for 'du'
and work out which parts of it you want to use
as the basis for your own perl module.


ciao
drieux

---

[Bob Showalter]

Dan Muey wrote:

> Howdy group.
>
> I have a need to get the size of a directory.
> I could just execute unix's du command (my $sz = `du -sh /usr`;)
> but was wondering if there's a better way to do it that is
> more portable.
> I looked on cpan but didn't see anythign that jumped out at me.

There's a group working on implementing a number of Unix utilities in Perl.
Here's their du page:

[url]http://www.perl.com/language/ppt/src/du/index.html[/url]

I don't know how portable it is...

[Dan Muey]

> Dan Muey wrote:

> >
> > Thanks. What I really want to do is avoid system commands

> completely.

> > I could always traverse the directory adding the size of each file
> > together and do that all in Perl with no system commands

> but I figured

> > there'd already be a Module or something like this, so I

> want to do it

> > that way. Somthign like:

>
> You mean something like (untested):
>
> use File::Find;
>
> my $dir = '/some/dir';
> my $size;
>
> find( sub { -f and ( $size += -s _ ) }, $dir );
>
> print "Directory '$dir' contains $size bytes\n";
>
>

Awesome John! Works splendedly, this is exactly what I needed!

>
> John
> --
> use Perl;
> program
> fulfillment

[David]

Dan Muey wrote:

>

>> On Tuesday, Nov 18, 2003, at 09:20 US/Pacific, Dan Muey wrote:
>>

>> > Howdy group.
>> >
>> > I have a need to get the size of a directory.
>> > I could just execute unix's du command (my $sz = `du -sh

>> /usr`;) but

>> > was wondering if there's a better way to do it that is more

>> portable.

>> > I looked on cpan but didn't see anythign that jumped out at me.
>> >

[snip]

> Thanks. What I really want to do is avoid system commands completely.

good decision.

> I could always traverse the directory adding the size of each file
> together and do that all in Perl with no system commands but I figured
> there'd already be a Module or something like this, so I want to do it
> that way. Somthign like:
>
> my $sz = $module->size("/home/joemama");

try Filesys::DiskFree

#!/usr/bin/perl -w
use strict;

use Filesys::DiskFree;

my $h = Filesys::DiskFree->new;

$h->df;
$h->device('/usr');

print "/usr has ",$h->avail('/usr')," bytes available\n";

__END__

prints:

/usr has 111111111 bytes available

david
--
s,.*,<<,e,y,\n,,d,y,.s,10,,s
..ss.s.s...s.s....ss.....s.ss
s.sssss.sssss...s...s..s....
....s.ss..s.sss..ss.s....ss.s
s.sssss.s.ssss..ss.s....ss.s
...s..sss.sssss.ss.sss..ssss.
...sss....s.s....ss.s....ss.s

,....{4},"|?{*=}_'y!'+0!$&;"
,ge,y,!#:$_(-*[./<-@{-},b-t,
..y...,$~=q~=?,;^_#+?{~,,$~=~
y.!-&*-/:-@^_{}.a-t ().;s,;,
);,g,s,s,$~s,g,y,y,%,,g,eval

[R. Joseph Newton]

david wrote:

> Dan Muey wrote:
>
> try Filesys::DiskFree
>
> #!/usr/bin/perl -w
> use strict;
>
> use Filesys::DiskFree;
>
> my $h = Filesys::DiskFree->new;
>
> $h->df;
> $h->device('/usr');
>
> print "/usr has ",$h->avail('/usr')," bytes available\n";
>
> __END__
>
> prints:
>
> /usr has 111111111 bytes available

On a Unix system. unfortunately, the module is not that portable, depending
on the Unix df command.

Joseph