Most powerful examples of Unix commands or scripts every programmer should know

Question

There are many things that all programmers should know, but I am particularly interested in the Unix/Linux commands that we should all know. For accomplishing tasks that we may

Answer 1

for card in `seq 1 8` ;do  
  for ts in `seq  1 31` ; do 
     echo $card $ts >>/etc/tuni.cfg;
   done
 done 

was better than writing the silly 248 lines of config by hand.

Neded to drop some leftover tables that all were prefixed with 'tmp'

for table in `echo show tables | mysql quotiadb |grep ^tmp` ; do
  echo drop table $table
done

Review the output, rerun the loop and pipe it to mysql