z/OS V1R9.0 UNIX System Services Command ... - Christian Grothoff

tcsh
password″ rot with !:s/rot/root to correct the spelling of ’root’ (but see “Spelling
correction” on page 631 for a different approach).
There is a special abbreviation for substitutions. ^, when it is the first character on
an input line, is equivalent to !:s^. Thus, we might have said ^rot^root to make the
spelling correction in the previous example. This is the only history substitution
which does not explicitly begin with !.
In csh as such, only one modifier may be applied to each history or variable
expansion. In tcsh, more than one may be used, for example
% mv wumpus.man /usr/man/man1/wumpus.1
% man !$:t:r
man wumpus
In csh, the result would be wumpus.1:r. A substitution followed by a colon may need
to be insulated from it with braces:
> mv a.out /usr/games/wumpus
> setenv PATH !$:h:$PATH
Bad ! modifier: $.
> setenv PATH !{-2$:h}:$PATH
setenv PATH /usr/games:/bin:/usr/bin:.
The first attempt would succeed in csh but fails in tcsh, because tcsh expects
another modifier after the second colon instead of $.
Finally, history can be accessed through the editor as well as through the
substitutions just described. The following commands search for events in the
history list and compile them into the input buffer:
v up-history
v down-history
v history-search-backward
v history-search-forward
v i-search-back
v i-search-fwd
v vi-search-back
v vi-search-fwd
v copy-prev-word
v insert-last-word
The toggle-literal-history editor command switches between the expanded and
literal forms of history lines in the input buffer. expand-history and expand-line
expand history substitutions in the current word and in the entire input buffer
respectively.
Alias substitution
The shell maintains a list of aliases which can be set, unset and printed by the
alias and unalias commands. After a command line is parsed into simple
commands (see “Command execution” on page 645) the first word of each
command, left-to-right, is checked to see if it has an alias. If so, the first word is
replaced by the alias. If the alias contains a history reference, it undergoes history
substitution as though the original command were the previous input line. If the
alias does not contain a history reference, the argument list is left untouched.
Thus if the alias for ls were ls -l the command ls /usrwould become ls -l /usr, the
argument list here being undisturbed. If the alias for lookup were grep !^
/etc/passwd then lookup bill would become grep bill /etc/passwd. Aliases can be
640 z/OS V1R9.0 UNIX System Services Command Reference