Looks good. If only my first script was so orderly...

Some things I'd do different: 

my $Usage = "usage: volume root_dir subvol timeframe dateformat keep\n
+";
@ARGV == 6 or die $Usage;  # we need six arguments

my (
  $subvol_to_snapshot_arg, # this
  $snap_root_dir_arg,      # assigns all variables
  $yabsm_subvol_name_arg,  # in one go
  $timeframe_arg,          # and leaves room
  $date_format_arg,        # to comment
  $snaps_to_keep_arg,      # what they are about
) = @ARGV;

[download]

That's a matter of style (and lazyness :-)

I'd use sprintf 

sub create_snapshot_name { 

  my ($min, $hr, $day, $mon, $yr) = (localtime())[1..5];

  $mon++;      # month count starts at zero. 
  $yr += 1900; # year represents years since 1900. 

  my @fields = 
    $date_format_arg   eq 'mm/dd/yyyy'
    ? ($mon, $day)
    : $date_format_arg eq 'dd/mm/yyyy'
      ? ($day,$mon)
      : die "$date_format_arg is not a valid date format";
      
  sprintf "day=%02d_%02d_%04d,time=%02d:%02d",@fields,$yr,$hr,$min;
}

[download]
which obsoletes the pad() subroutine. Expressing the if/else/elsif as a construct of ternaries (COND ? IF_TRUE : IF_FALSE) is, again, a matter of style. The sprintf being the last expression eliminates the need for an explicit return.

edit:

Since the documentation is contained in the script, and it states

This script should not be used by the end user.

[download]

you could stick the following directive into it up front 

exec "pod2man $0" if -t; # display manual page if invoked from termina
+l

[download]

which can be overridden redirecting /dev/null into it as STDIN.

perl -le'print map{pack c,($-++?1:13)+ord}split//,ESEL'

In reply to Re: looking for feedback on my first script by shmem
in thread looking for feedback on my first script by thirtySeven

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.