bash join lines based on id code example

Example: combine all lines with same value of a column unix

cat FILENAME | perl -e 'foreach $Line (<STDIN>) { @Cols=($Line=~/^\s*(\d+)\s*(.*?)\s*$/); push(@{$Link{$Cols[0]}}, $Cols[1]); } foreach $List (values %Link) { print join("\t", @{$List})."\n"; }'