Fortunately, the original maxim that "history repeats itself" is more appropriate to UNIX.
Most shells include a powerful history mechanism that lets you recall and repeat past commands, potentially editing them before execution. This can be a godsend, especially when typing a long or complex command.
All that is needed to set C shell history in motion is a command like this in your .cshrc file:
The history command lists the saved commands, each with an identifying number. [In csh and bash , you can show just the last few commands by typing a number, too. For instance, history 20 shows your last 20 commands. -JP ] (It's also possible to configure the shells to print the history number of each command .)
you can repeat a past command by typing its
number (or its name) preceded by an exclamation point (
Most shells - except the original Bourne and C shells - also have
[Interactive editing might seem to be better than typing