I have a requirement to parse the etime field of solaris ps command. It looks like this (from man ps) [[dd-]hh:]mm:ss The leading two fields (days and hours) are optional. My first attempt was a re which looks pretty nasty: 
for ($etime){
  my ($dd,$hh,$mm,$ss)=()
  # see man ps etime looks like [[dd-]hh:]mm:ss
  if ( /^(?:(?:(\d{1,2})-){0,1})(?:(?:(\d{2}):){0,1})(\d{1,2}):(\d{2})
+$/
){
    $dd = $1 || ''; $hh = $2 || ''; $mm = $3; $ss = $4;
    $etime_secs= $ss+($mm*60)+($hh*60*60)+($dd*24*60*60);
  }
}

[download]
I am sure the re can be improved but really the problem seemed to be begging for a split: 
for ($etime){
  # see man ps etime looks like [[dd-]hh:]mm:ss
  # if either $dd and $hh are not present then they will eat 
  # up the $mm & $ss so split on a non digit and reverse it:
  my ($ss, $mm, $hh, $dd)= reverse split /\D/;
  $hh += 0;   # stop warning as $hh may not be initialised
  $dd += 0;   # same as $hh :)
  $etime_secs= $ss+($mm*60)+($hh*60*60)+($dd*24*60*60);
}

[download]
Which is much nicer though I am just itching to get rid of the lines to make sure $hh and $dd are initialised :) Can any-one see a better way?

--
Life is a tale told by an idiot -- full of sound and fury, signifying nothing. William Shakespeare, Macbeth

In reply to parsing etime field from solaris ps by greenFox

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