I need to verify there is no duplicate UIDs in the /etc/passwd file. My plan was to sort the file by the UID, and then check for lines with UID = to previous line. Is this the best way? I was trying this code: 
#!/usr/bin/perl -w
#<SortPW2.pl> /etc/passwd sort by UID

$file="/etc/passwd";
my @array = do { local( @ARGV, $/ ) = $file ; <> } ;
#my @array = (
          #'555900:user:lee:0:23030',
          #'3520916:user:joe:0:20487',
          #'395284:user:richard:3:17557',
          #'807060:group:smith:0:20573',
          #'381940:home:kimble:1:625',
#);

my @sorted = map {$_->[0]}
             sort {$a->[1] <=> $b->[1] || $a->[1] cmp $b->[1]}
             map {[$_,(split':')[0]]} @array;

print "$_\n" for @sorted;

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The commented out code works, but the modification to source the array from /etc/passwd fails. Is it the line feeds? how would I remove them? Or is there a better way. All help appreciated. Thanx

In reply to Sort passwd by UID by Saved

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