Linux and Unix for, foreach and repeat
Shell built-in functions to repeatedly execute action(s) for a selected number of times.
for word [ in wordlist ... ] ; do actions ; done
foreach word ( wordlist )
[ ... ]
repeat count command
for file in *.txt ; do wc -l $file ; done
In ksh (Korn Shell) would do a word count of the files *.txt until done and would return results similar to the below example.