csh.1

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or
.I while.
The remaining commands on the current line are executed.
Multi-level breaks are thus possible by writing them all on one line.
.HP 5
.B  breaksw
.NXR "breaksw command (csh)"
.br
Causes a break from a
.I switch,
resuming after the
.I endsw.
.HP 5
.BR case " label:"
.NXR "case command (csh)" 
.br
A label in a
.I switch
statement as discussed below.
.HP 5
.B  cd
.br
.ns
.HP 5
.BR cd " name"
.NXR "cd command (csh)"
.br
.ns
.HP 5
.B  chdir
.NXR "chdir command (csh)"
.br
.ns
.HP 5
.BR chdir " name"
.br
Change the shell's working directory to directory
.I name.
If no argument is given then change to the home directory of the user.
.br
If
.I name
is not found as a subdirectory of the current directory (and does not begin
with `/', `./' or `../'), then each
component of the variable
.I cdpath
is checked to see if it has a subdirectory
.I name.
Finally, if all else fails but
.I name
is a shell variable whose value begins with `/', then this
is tried to see if it is a directory.
.HP 5
.B  continue
.NXR "continue command (csh)"
.br
Continue execution of the nearest enclosing
.I while
or
.I foreach.
The rest of the commands on the current line are executed.
.HP 5
.B  default:
.br
Labels the default case in a
.I switch
statement.
The default should come after all
.I case
labels.
.HP 5
.BR "dirs"
.NXR "dir command (csh)"
.br
Prints the directory stack; the top of the stack is at the left,
the first directory in the stack being the current directory.
.HP 5
.BR echo " wordlist"
.NXR "echo command (csh)"
.br
.ns
.HP 5
.BR "echo \-n" " wordlist"
.br
The specified words are written to the shell's standard output, separated
by spaces, and terminated with a new line unless the
.B \-n
option is specified.
.HP 5
.B  else
.br
.ns
.HP 5
.B  end
.br
.ns
.HP 5
.B  endif
.br
.ns
.HP 5
.B  endsw
.br
See the description of the
.I foreach,
.I if,
.I switch,
and
.I while
statements below.
.HP 5
.BR eval " arg ..."
.NXR "eval command (csh)"
.br
As in sh(1).
The arguments are read as input to the shell and the resulting
command(s) executed in the context of the current shell.
This is usually used to execute commands
generated as the result of command or variable substitution, since
parsing occurs before these substitutions.  See
.MS test 1
for an example of using
.IR eval .
.HP 5
.BR exec " command"
.NXR "exec command (csh)"
.br
The specified command is executed in place of the current shell.
.HP 5
.B  exit
.br
.ns
.HP 5
.BR exit (expr)
.NXR "exit command (csh)"
.br
The shell exits either with the value of the
.I status
variable (first form) or with the value of the specified
.I  expr
(second form).
.HP 5
.B fg
.NXR "fg command (csh)"
.br
.ns
.HP 5
\fBfg\ %\fRjob\ ...
.br
Brings the current or specified jobs into the foreground, continuing them if
they were stopped.
.HP 5
.BR foreach " name (wordlist)"
.NXR "foreach command (csh)"
.br
.ns
.HP 5
\    ...
.br
.ns
.HP 5
.B  end
.NXR "end command (csh)"
.br
The variable
.I name
is successively set to each member of
.I wordlist
and the sequence of commands between this command and the matching
.I end
are executed.
(Both
.I foreach
and
.I end
must appear alone on separate lines.)
.IP
The built-in command
.I continue
may be used to continue the loop prematurely and the built-in
command
.I break
to terminate it prematurely.
When this command is read from the terminal, the loop is read up once
prompting with `?' before any statements in the loop are executed.
If you make a mistake typing in a loop at the terminal you can rub it out.
.HP 5
.BR glob " wordlist"
.NXR "glob command (csh)"
.br
Like
.I echo
but no `\e' escapes are recognized and words are delimited
by null characters in the output.
Useful for programs which wish to use the shell to file name expand a list
of words.
.HP 5
.BR goto " word"
.NXR "goto command (csh)"
.br
The specified
.I word
is file name and command expanded to yield a string of the form `label'.
The shell rewinds its input as much as possible
and searches for a line of the form `label:'
possibly preceded by blanks or tabs.
Execution continues after the specified line.
.HP 5
.BR hashstat
.NXR "hashstat command (csh)"
.br
Print a statistics line indicating how effective the internal hash
table has been at locating commands (and avoiding
.IR exec 's).
An
.I exec
is attempted for each component of the
.I path
where the hash function indicates a possible hit, and in each component
which does not begin with a `/'.
.HP 5
.B  history
.NXR "history command (csh)"
.br
.ns
.HP 5
.BI history " n"
.br
.ns
.HP 5
.BI "history \-r" " n"
.br
.ns
.HP 5
.BI "history \-h" " n"
.br
Displays the history event list; if \fIn\fR is given only the
.I n
most recent events are printed.
The
.B \-r
option reverses the order of printout to be most recent first
rather than oldest first.
The
.B \-h
option causes the history list to be printed without leading numbers.
This is used to produce files suitable for sourcing using the \-h
option to
.IR source .
.HP 5
.BR if " (expr) command"
.NXR "if command (csh)"
.br
If the specified expression evaluates true, then the single
.I  command
with arguments is executed.
Variable substitution on
.IR command ""
happens early, at the same
time it does for the rest of the
.I if
command.
.I Command
must be a simple command, not
a pipeline, a command list, or a parenthesized command list.
Input/output redirection occurs even if
.I expr
is false, when command is
.B not
executed (this is a bug).
.HP 5
.BR if " (expr) " "then"
.br
.ns
.HP 5
\    ...
.br
.ns
.HP 5
.BR else " " "if\fR (expr2) \fBthen"
.NXR "else command (csh)"
.br
.ns
.HP 5
\    ...
.br
.ns
.HP 5
.B  else
.br
.ns
.HP 5
\    ...
.br
.ns
.HP 5
.B  endif
.NXR "endif command (csh)"
.br
If the specified
.IR expr ""
is true then the commands to the first
.I else
are executed; else if
.IR expr2 ""
is true then the commands to the
second else are executed, etc.
Any number of
.I else-if
pairs are possible; only one
.I endif
is needed.
The
.I else
part is likewise optional.
(The words
.I else
and
.I endif
must appear at the beginning of input lines;
the
.I if
must appear alone on its input line or after an
.I else.)
.HP 5
.B jobs
.NXR "jobs command (csh)"
.br
.ns
.HP 5
.B "jobs \-l"
.br
Lists the active jobs; given the
.B \-l
options lists process id's in addition to the normal information.
.HP 5
\fBkill %\fRjob
.NXR "kill command (csh)"
.br
.ns
.HP 5
\fBkill\ \-\fRsig\ \fB%\fRjob\ ...
.br
.ns
.HP 5
\fBkill\fR\ pid
.br
.ns
.HP 5
\fBkill\ \-\fRsig\ pid\ ...
.br
.ns
.HP 5
\fBkill\ \-l\fR
.br
Sends either the TERM (terminate) signal or the
specified signal to the specified jobs or processes.
Signals are either given by number or by names (as given in
.I /usr/include/signal.h,
stripped of the prefix ``SIG'').
The signal names are listed by ``kill \-l''.
There is no default, saying just `kill' does not
send a signal to the current job.
If the signal being sent is TERM (terminate) or HUP (hangup),
then the job or process will be sent a CONT (continue) signal as well.
.HP
\fBlimit\fR
.NXR "limit command (csh)"
.br
.ns
.HP 5
\fBlimit\fR \fIresource\fR
.br
.ns
.HP 5
\fBlimit\fR \fIresource\fR \fImaximum-use\fR
.br
Limits the consumption by the current process and each process
it creates to not individually exceed \fImaximum-use\fR on the
specified \fIresource\fR.  If no \fImaximum-use\fR is given, then
the current limit is printed; if no \fIresource\fR is given, then
all limitations are given.
.IP
The following resources can be controlled:
.IP \(bu 5
\fIcputime\fR (maximum number of cpu-seconds to be used by each process) 
.IP \(bu 5
\fIfilesize\fR (largest single file which can be created)
.IP \(bu 5
\fIdatasize\fR (the maximum growth of the data+stack region by
.MS sbrk 2
beyond the end of the program text)
.IP \(bu 5
\fIstacksize\fR (the maximum size of the automatically-extended stack region)
.IP \(bu 5
\fIcoredumpsize\fR (the size of the largest core dump that can be created).
.IP \(bu 5
\fImemoryuse\fR (the maximum amount of main memory a process is allowed
to occupy)
.IP
The \fImaximum-use\fR may be given as a (floating point or integer)
number followed by a scale factor.  For all limits other than \fIcputime\fR
the default scale is `k' or `kilobytes' (1024 bytes);
a scale factor of `m' or `megabytes' may also be used.
For
.I cputime
the default scaling is `seconds', while `m' for minutes
or `h' for hours, or a time of the form `mm:ss' giving minutes
and seconds may be used.
.IP
For both \fIresource\fR names and scale factors, unambiguous prefixes
of the names suffice.
.HP 5
.B  login
.NXR "login command (csh)"
.br
Terminate a login shell, replacing it with an instance of
.B /bin/login.
This is one way to log off, included for compatibility with
.MS sh 1 .
.HP 5
.B  logout
.NXR "logout command (csh)"
.br
Terminate a login shell.
Especially useful if
.I ignoreeof
is set.
.HP 5
.B  nice
.NXR "nice command (csh)"
.br
.ns
.HP 5
.BR nice " \+number"
.br
.ns
.HP 5
.BR nice " command"
.br
.ns
.HP 5
.BR nice " \+number command"
.br
The first form sets the
.I nice
for this shell to 4.
The second form sets the
.I nice
to the given number.
The final two forms run command at priority 4 and
.I number
respectively.
The super-user may specify negative niceness by using `nice \-number ...'.
Command is always executed in a sub-shell, and the restrictions
place on commands in simple
.I if
statements apply.
.HP 5
.B  nohup
.NXR "nohup command (csh)"
.br
.ns
.HP 5
.BR "nohup" " command"
.br
The first form can be used in shell scripts to cause hangups to be