On Fri, Dec 30, 2011 at 6:00 AM, ankush grover <ankushcentos@xxxxxxxxx> wrote: > Hi Friends, > > I am trying to write a shell script which can merge the 2 columns into > 3rd one on Centos 5. The file is very long around 31200 rows having > around 1370 unique groups and around 12000 unique user-names. > The 1st column is the groupname and then 2nd column is the user-name. > > 1st Column (Groupname) 2nd Column (username) > admin ankush > admin amit > powerusers dinesh > powerusers jitendra > > > > > The desired output should be like this > > admin: ankush, amit > powerusers: dinesh, jitendra > > > There are commands available but not able to use it properly to get > the desired output. Please help me > Here's a perl approach: #!/usr/bin/perl my ($group,$name); my %groups=(); while (<>) { chomp(); ($group,$name) = split(/ /); push @{ $groups{$group} }, $name; } foreach $group (sort keys(%groups)) { print "$group: " . join("," , @{$groups{$group}}) ."\n"; } Cat or redirect the list to the program input, output is on stdout. -- Les Mikesell lesmikesell@xxxxxxxxx _______________________________________________ CentOS mailing list CentOS@xxxxxxxxxx http://lists.centos.org/mailman/listinfo/centos