The mkdir builtin creates the directory with mode 0777 if the mask argument is omitted. There is no mode argument.

What do you mean by 'size' in the title? An empty directory has a size of one disk block.

Update: ++podmaster reminds me of umask, which sets the current default mask applied to the creation of all new files (including directories), returning the old default mask to ease its restoration.

Update 2: =sjs=, your perl -e'mkdir{"t")' works for me. Are you running some blighted shell that demands double quotes for -e arguments? If so, try <code>perl -e"mkdir(q(t))"

After Compline,
Zaxo

when I

> perl -e 'mkdir("t")'
Not enough arguments for mkdir at -e line 1, at end of line
Execution of -e aborted due to compilation errors.
[download]

What do you mean??

If you're wanting to sum the sizes of all files within a directory, this should do it:

my $dir      = '/path/to/dir';
my $dir_size = 0;
my $file;

opendir DIR, $dir or die "Unable to open $dir: $!\n";
$dir_size += -s "$dir/$file" while defined( $file = readdir DIR );
closedir DIR;
print $dir_size;
[download]

This does not descend into subdirectories, though.

#!/usr/bin/perl -w
use File::Find;
use strict;
my $total = 0;
my $dir   = $ARGV[0] || '.';
find sub {$total += -s $_;},$dir;
my $megs  = sprintf "%5.2f",($total/(1024*1024));
print "Total size of files in $dir:$megs Mbytes\n";
[download]