Intel XENIX 286 Programmers Guide (86) - Tenox.tc

XENIX Programming csh: C Shell
Using Built-In Commands
This section explains how to use some of the built-in C shell commands.
The alias command (see "Using Aliases" above) is used to assign new aliases and to
display existing aliases. If given no arguments, alias prints the list of current aliases.
alias can also be given one argument to show the current alias for a given string of
characters. For example
alias Is
prints the current alias for the string "Is".
The history command displays the contents of the history list. The numbers given with
the history events can be used to reference previous events difficult to reference
contextually. There is also a C shell variable named prompt. By placing an exclamation
point (!) in its value the C shell will substitute the nu mber of the current command in
the history list. You can use this nu mber to refer to a command in a history
substitution. For example, you could type
set prompt = I \ ! % I
Nate that the exclamation mark (!) had to be escaped even within single quotes.
The logout command is used to terminate a login C shell that has ignoreeof set.
The rehash command causes the C shell to recompute a table of command locations.
This is necessary if you add a command to a directory in the current C shell's search
path and want the C shell to find it, since otherwise the hashing algorithm may tell the
C shell that the command wasn't in that directory when the hash table was computed.
The repeat command is used to repeat a command several times. For example, to make
five copies of the file one in the file five you could type
repeat 5 cat one > > five
The setenv command can be used to set variables in the environment. Thus
setenv TERM adm3a
sets the value of the environment variable TERM to "adm3a". The env command prints
out the environment. For example:
% env
HOME =/usr/bill
SHELL = /bin/csh
PATH = :/usr/ucb:/bin:/usr/bi n:/usr/local
TERM = adm3a
USER = bill
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