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TCSH(1) TCSH(1)
NAME
tcsh - shell with file name completion and command line editing
SYNOPSIS
tcsh [ -bcdefimnqstvVxX ] [ argument ... ]
or
tcsh -l
OS/Dependent Options
tcsh [ -F ] [ -Dname[=value] ]
DESCRIPTION
Tcsh is an enhanced version of the Berkeley UNIX C shell csh(1). It
behaves similarly to the C shell, except for the added utilities of:
1) Command line editing using Emacs-style commands.
2) Visual step up/down through the history list.
3) Terminal mode sanity checking and resetting.
4) Interactive command, file name and user name completion.
5) File/directory/user list in the middle of a typed command.
6) Spelling correction of command, file, and user names.
7) Lookup of command documentation in the middle of a typed command.
8) Enhanced history mechanism.
9) Automatic locking/logout after long periods of idle time.
10) Automatic execution of a single command prior to printing each
prompt.
11) Automatic periodic command execution.
12) A new syntax for the prompt, and the ability to set the prompt for
"while" and "for" loops.
13) Time stamps in the history list.
14) An addition to the syntax of filenames to access entries in the
directory stack, and the ability treat symbolic links in a sane way
when changing directories.
15) The ability to watch for logins and logouts by user or terminal on
the machine.
16) A scheduled event list, which specifies commands which are to be
executed at given times.
17) A new builtin that does a subset of ls(1).
18) An addition to the file expression syntax for a character not in a
set of characters and the ability to negate a globbing pattern.
19) New automatically initialized environment variables HOST and
HOSTTYPE.
20) Commands for debugging terminal capabilities.
21) Searching for the visual history mechanism.
22) New builtins for the which(1) and where commands.
23) Restarting a stopped editor with two keystrokes.
24) Status line support
25) Automatic execution of a command when the current working directory
is changed.
26) Native Language System support.
27) Automatic process time reporting.
28) OS Dependent Builtin Support
29) Automatic window size adjustment
30) Input files
31) Additional/Undocumented Options
32) Enhanced history/variable modifier expansion
33) Programmable completion.
34) Enhanced file inquiry operator.
35) Readonly variables.
36) Implicit cd for directory names entered as commands.
For a description of standard C-shell features, see the csh manual page.
1. COMMAND LINE EDITING
Commands that the user types in may be edited using the same control
characters that Gnu Emacs or vi uses. Arrow and function key sequences
are also allowed. Tcsh allows this by setting the terminal to `CBREAK'
mode and reading the input one character at a time.
There is a new shell command, bindkey, that allows the user to redefine
what any key does, or find out what any or all of the keys do.
Syntax: bindkey [ -a ] [ -c ] [ -s ] [ -v ] [ -e ] [ -d ] [ -k ] [ -l ] [
-r ] [ -- ] [ [ in-string | key-name ] [ out-string | command ]]
If no values are given all bindings are listed. If only in-string is
given, bindings for the in-string is listed.
Otherwise it binds the in-string to the given out-string or command. If
out-string, this is treated as input to tcsh when in-string is typed.
This may be used recursively to currently a level of 10 deep.
There are two basic key maps: the normal and alternative one. The
alternative is used by VI command mode. For multi-character input the
basic key maps contains a sequence-lead-in for the first character in the
input.
Options:
-a bind in-string in alternative key map
-s bind an out-string instead of a command
-c bind a unix command instead of a command
-v bind for default VI-mode
-e bind for default emacs-mode
-k interpret in-string as a symbolic arrow key name
-d bind to compiled in default
-l list functions available with short description
-r remove the binding of in-string
In strings control characters may be written as caret- and
backslash ("\") is used to escape a character as follows:
\a bell character
\n line feed (new line)
\b back space
\t horizontal tab
\v vertical tab
\f form feed
\r carriage return
\e escape
\nnn character code in octal
In all other cases \ escapes the following character. Needed for escaping
the special meaning of \ and ^. Delete is written as "^?" (caret-
question mark).
Tcsh always binds the arrow keys as defined by the termcap entry to:
up arrow up-history
down arrow down-history
right arrow forward-char
left arrow backward-char
except where these bindings would alter other single character bindings.
If this is not desired one can avoid the automatic arrow key binding
using settc to change the arrow key escape sequences to the empty string.
The ansi/vt100 sequences for arrow keys are always bound.
The following is a list of the default emacs and vi bindings. Characters
with the 8th bit set are written as M-. Note however, that
unlike with the old bind command (see below), the syntax M-
has no special meaning to the bindkey command, and the bindings for the
sequence escape+ and M- as given below are handled
separately (although the default bindings are the same). The printable
ascii characters not mentioned in the list are bound to the self-insert-
command function, which just inserts the given character literally into
the input line. The remaining characters are bound to the undefined-key
function, which only causes a beep (unless nobeep is set, of course).
EMACS bindings
"^@" -> set-mark-command
"^A" -> beginning-of-line
"^B" -> backward-char
"^C" -> tty-sigintr
"^D" -> delete-char-or-list
"^E" -> end-of-line
"^F" -> forward-char
"^G" -> is undefined
"^H" -> backward-delete-char
"^I" -> complete-word
"^J" -> newline
"^K" -> kill-line
"^L" -> clear-screen
"^M" -> newline
"^N" -> down-history
"^O" -> tty-flush-output
"^P" -> up-history
"^Q" -> tty-start-output
"^R" -> redisplay
"^S" -> tty-stop-output
"^T" -> transpose-chars
"^U" -> kill-whole-line
"^V" -> quoted-insert
"^W" -> kill-region
"^X" -> sequence-lead-in
"^Y" -> yank
"^Z" -> tty-sigtsusp
"^[" -> sequence-lead-in
"^\" -> tty-sigquit
"^]" -> tty-dsusp
" " to "/" -> self-insert-command
"0" to "9" -> digit
":" to "~" -> self-insert-command
"^?" -> backward-delete-char
EMACS Multi-character and 8 bit bindings
"^[^D" or "M-^D" -> list-choices
"^[^H" or "M-^H" -> backward-delete-word
"^[^I" or "M-^I" -> complete-word
"^[^L" or "M-^L" -> clear-screen
"^[^Z" or "M-^Z" -> run-fg-editor
"^[^[" or "M-^[" -> complete-word
"^[^_" or "M-^_" -> copy-prev-word
"^[ " or "M- " -> expand-history
"^[!" or "M-!" -> expand-history
"^[$" or "M-$" -> spell-line
"^[0" or "M-0" -> digit-argument
"^[1" or "M-1" -> digit-argument
"^[2" or "M-2" -> digit-argument
"^[3" or "M-3" -> digit-argument
"^[4" or "M-4" -> digit-argument
"^[5" or "M-5" -> digit-argument
"^[6" or "M-6" -> digit-argument
"^[7" or "M-7" -> digit-argument
"^[8" or "M-8" -> digit-argument
"^[9" or "M-9" -> digit-argument
"^[?" or "M-?" -> which-command
"^[B" or "M-B" -> backward-word
"^[C" or "M-C" -> capitalize-word
"^[D" or "M-D" -> delete-word
"^[F" or "M-F" -> forward-word
"^[H" or "M-H" -> run-help
"^[L" or "M-L" -> downcase-word
"^[N" or "M-N" -> history-search-forward
"^[P" or "M-P" -> history-search-backward
"^[R" or "M-R" -> toggle-literal-history
"^[S" or "M-S" -> spell-word
"^[U" or "M-U" -> upcase-word
"^[W" or "M-W" -> copy-region-as-kill
"^[_" or "M-_" -> insert-last-word
"^[b" or "M-b" -> backward-word
"^[c" or "M-c" -> capitalize-word
"^[d" or "M-d" -> delete-word
"^[f" or "M-f" -> forward-word
"^[h" or "M-h" -> run-help
"^[l" or "M-l" -> downcase-word
"^[n" or "M-n" -> history-search-forward
"^[p" or "M-p" -> history-search-backward
"^[r" or "M-r" -> toggle-literal-history
"^[s" or "M-s" -> spell-word
"^[u" or "M-u" -> upcase-word
"^[w" or "M-w" -> copy-region-as-kill
"^[^?" or "M-^?" -> backward-delete-word
"^X^X" -> exchange-point-and-mark
"^X*" -> expand-glob
"^X$" -> expand-variables
"^XG" -> list-glob
"^Xg" -> list-glob
"^Xn -> normalize-path
"^XN -> normalize-path
VI Insert Mode functions
"^@" -> is undefined
"^A" -> beginning-of-line
"^B" -> backward-char
"^C" -> tty-sigintr
"^D" -> list-or-eof
"^E" -> end-of-line
"^F" -> forward-char
"^G" -> list-glob
"^H" -> backward-delete-char
"^I" -> complete-word
"^J" -> newline
"^K" -> kill-line
"^L" -> clear-screen
"^M" -> newline
"^N" -> down-history
"^O" -> tty-flush-output
"^P" -> up-history
"^Q" -> tty-start-output
"^R" -> redisplay
"^S" -> tty-stop-output
"^T" -> transpose-chars
"^U" -> backward-kill-line
"^V" -> quoted-insert
"^W" -> backward-delete-word
"^X" -> expand-line
"^Y" -> tty-dsusp
"^Z" -> tty-sigtsusp
"^[" -> vi-cmd-mode
"^\" -> tty-sigquit
" " to "~" -> self-insert-command
"^?" -> backward-delete-char
VI Command Mode functions
"^@" -> is undefined
"^A" -> beginning-of-line
"^B" -> is undefined
"^C" -> tty-sigintr
"^D" -> list-choices
"^E" -> end-of-line
"^F" -> is undefined
"^G" -> list-glob
"^H" -> backward-char
"^I" -> vi-cmd-mode-complete
"^J" -> newline
"^K" -> kill-line
"^L" -> clear-screen
"^M" -> newline
"^N" -> down-history
"^O" -> tty-flush-output
"^P" -> up-history
"^Q" -> tty-start-output
"^R" -> redisplay
"^S" -> tty-stop-output
"^T" -> is undefined
"^U" -> backward-kill-line
"^V" -> is undefined
"^W" -> backward-delete-word
"^X" -> expand-line
"^[" -> sequence-lead-in
"^\" -> tty-sigquit
" " -> forward-char
"!" -> expand-history
"$" -> end-of-line
"*" -> expand-glob
"+" -> down-history
";" -> vi-repeat-char-fwd
"," -> vi-repeat-char-back
"-" -> up-history
"." -> is undefined
"/" -> vi-search-back
"0" -> vi-zero
"1" to "9" -> digit-argument
"?" -> vi-search-fwd
"@" -> is undefined
"A" -> vi-add-at-eol
"B" -> vi-word-back
"C" -> change-till-end-of-line
"D" -> kill-line
"E" -> vi-endword
"F" -> vi-char-back
"I" -> vi-insert-at-bol
"J" -> history-search-forward
"K" -> history-search-backward
"N" -> vi-search-back
"O" -> sequence-lead-in
"R" -> vi-replace-mode
"S" -> vi-substitute-line
"T" -> vi-charto-back
"U" -> is undefined
"V" -> expand-variables
"W" -> vi-word-fwd
"X" -> backward-delete-char
"[" -> sequence-lead-in
"\^" -> beginning-of-line
"a" -> vi-add
"b" -> backward-word
"c" -> is undefined
"d" -> vi-delmeta
"e" -> vi-eword
"f" -> vi-char-fwd
"h" -> backward-char
"i" -> vi-insert
"j" -> down-history
"k" -> up-history
"l" -> forward-char
"m" -> is undefined
"n" -> vi-search-fwd
"r" -> vi-replace-char
"s" -> vi-substitute-char
"t" -> vi-charto-fwd
"u" -> vi-undo
"v" -> expand-variables
"w" -> vi-beginning-of-next-word
"x" -> delete-char
"~" -> change-case
"^?" -> backward-delete-char
"M-?" -> run-help
"M-[" -> sequence-lead-in
"M-O" -> sequence-lead-in
VI Multi-character bindings
"^[?" -> run-help
In tcsh there are two input modes: insert and overwrite. All characters
that are bound to the self-insert-command either get inserted or
overwrite what was under the cursor depending on the input mode. In emacs
one can toggle between modes using the overwrite-mode function, and in VI
one can use any of the replace mode commands. By default the mode is
preserved between input lines. To specify a default mode that can be
enforced at the beginning of each command line, the variable inputmode
can be set to either insert or overwrite.
There is also an older version of bindkey called bind, that allows the
user to redefine what any key does, or find out what any or all of the
keys do. This is retained for compatibility reasons.
If given two arguments bind binds the function (first argument) to the
given key (second argument). The key may be: the direct character or a
caret- combination, which is converted to control-; M-
for an escaped character; or F- for a function key. For
the last of these, the function key prefix must be bound to the function
"sequence-lead-in" and the string specified to the bind command must not
include this prefix.
If given one argument bind takes the argument as the name for a key and
tells what that key does. As a special case, the user can say
bind emacs
or
bind vi
to bind all the keys for Emacs or vi mode respectively.
If given no arguments bind tells what all of the keys do. If you give
bind the single argument of 'defaults', it resets each key to its default
value (see the above list).
2. VISUAL HISTORY
The keys ^P and ^N are used to step up and down the history list. If the
user has typed in the following:
> ls
foo bar
> echo mumble
mumble
>
then enters ^P, the shell will place "echo mumble" into the editing
buffer, and will put the cursor at the end of the line. If another ^P is
entered, then the editing line will change to "ls". More ^Ps will make
the bell ring, since there are no more lines in the history. ^N works
the same way, except it steps down (forward in time).
An easy way to re-do a command is to type ^P followed by Return. Also,
pieces of previous commands can be assembled to make a new command. The
commands that work on regions are especially useful for this.
^P and ^N actually only copy commands from out of the history into the
edit buffer; thus the user may step back into the history and then edit
things, but those changes do not affect what is actually in tcsh 's
history.
Another way to recall (parts of) history commands is via the 'expand-
history' function. A variation of the 'expand-history' function is called
'magic-space'. This function expands csh history, and always appends a
space. Magic-space thus can be bound to , to automatically expand
csh history. Expand-history is normally bound to M- and magic-
space is not bound.
3. TTY MODE SANITY
As part of the editor, tcsh does a check and reset of the terminal mode
bits. If the speed has been changed, then tcsh will change to using that
speed. Tcsh will also obey changes in the padding needed by the tty.
Also, the shell will automatically turn off RAW and CBREAK (on systems
that use termio(7) it will turn on ICANON) modes, and will turn on the
tty driver's output processing (OPOST).
The list of the tty modes that are always set or cleared by tcsh can be
examined and modified using the setty builtin. The setty display is
similar to stty(1), and varies depending on the system's tty driver.
Modes that tcsh will always try to set are shown as +mode . Modes that
tcsh will always try to clear are shown as -mode and modes that tcsh will
track and allow to be modified are not shown by default, or if the -a
flag is given, are shown without a leading sign. For tty characters, -
char disables the tty character, while +char protects the tty character
from being changed.
Setty can be used to control the three different modes tcsh uses for the
tty. The default mode displayed is the "execute" mode which is used when
tcsh executes commands. The two other modes are the "edit" mode and the
"quote" mode. The "edit" mode is used for command line editing, and the
"quote" mode is used when entering literal characters. The "execute" mode
can be specified with -x , the "edit" mode with -d , and the "quote" mode
with -q For example if one wants to set the echok flag and let the echoe
pass unchanged:
> setty
iflag:-inlcr -igncr +icrnl
oflag:+opost +onlcr -onlret
cflag:
lflag:+isig +icanon +echo +echoe -echok -echonl -noflsh
+echoctl -flusho +iexten
chars:
> setty +echok echoe
> setty
iflag:-inlcr -igncr +icrnl
oflag:+opost +onlcr -onlret
cflag:
lflag:+isig +icanon +echo +echok -echonl -noflsh +echoctl
-flusho +iexten
chars:
4. WORD COMPLETION
In typing commands, it is no longer necessary to type a complete name,
only a unique abbreviation is necessary. When you type a TAB to tcsh it
will complete the name for you, echoing the full name on the terminal
(and entering it into the edit buffer). If the prefix you typed matches
no name, the terminal bell is rung, unless the variable nobeep is set.
The name may be partially completed if the prefix matches several longer
names. If this is the case, the name is extended up to the point of
ambiguity, and the bell is rung. This works for file names, command
names, shell variables and the ~ user name convention. The variable
fignore may be set to a list of suffixes to be disregarded during
completion.
Example
Assume the current directory contained the files:
DSC.TXT bin cmd lib memos
DSC.NEW chaos cmtest mail netnews
bench class dev mbox new
The command:
> gnumacs ch[TAB]
would cause tcsh to complete the command with the file name chaos. If
instead, the user had typed:
> gnumacs D[TAB]
tcsh would have extended the name to DSC and rung the terminal bell,
indicating partial completion. However, if fignore had previously been
set to a list containing .NEW as one element, e.g. ( .o .NEW ), tcsh
would have completed the `D' to DSC.TXT.
File name completion works equally well when other directories are
addressed. Additionally, tcsh understands the C shell tilde (~)
convention for home directories. In addition it caches tilde name
references for fast access. This cache can be flushed by using the
builtin rehash. Thus,
> cd ~speech/data/fr[TAB]
does what one might expect. This may also be used to expand login names
only. Thus,
> cd ~sy[TAB]
expands to
> cd ~synthesis
Command names may also be completed, for example,
> gnum[TAB]
will expand to "gnumacs" (assuming that there are no other commands that
begin with "gnum").
Shell and environment variables are recognized also and in addition they
can be expanded:
> set local=/usr/local
> echo $lo[TAB]
will expand to "$local/". Note that a slash is appended because the
expanded variable points to a directory. Also:
> set local=/usr/local
> echo $local/[^D]
bin/ etc/ lib/ man/ src/
will correctly list the contents of /usr/local. Shell and environment
variables can also be expanded via the expand-variables function:
> echo $local/[^X$]
> echo /usr/local/
Completion also works when the cursor is in the middle of the line,
rather than just the end. All of the text after the cursor will be
saved, the completion will work (possibly adding to the current name),
and then the saved text will be restored in place, after the cursor.
The behavior of the completion can be changed by the setting of several
shell variables:
Setting the recexact variable makes an exact command be expanded rather
than just ringing the bell. For example, assume the current directory
has two sub-directories called foo and food, then with recexact set the
following could be done:
> cd fo[TAB]
to ...
> cd foo[TAB]
to ...
> cd foo/
rather than beeping on the second TAB.
If the autolist variable is set, invoking completion when several choices
are possible will automatically list the choices, effectively merging the
functionality described in the next section into the completion
mechanism. If autolist is set to "ambiguous", then tcsh will only list
the choices if there were no new characters added in the completion
operation.
The "noise level" can be controlled by the value that matchbeep is set
to: With matchbeep=nomatch, completion will only beep if there are no
matching names; with matchbeep=ambiguous, completion will also beep if
there are many possible matches; with matchbeep=notunique, completion
will also beep when there is an exact match but there are other, longer,
matches (see recexact). With matchbeep=never or set to any other value
completion will never beep. If matchbeep is not set it defaults to
ambiguous.
If the autoexpand variable is set, the expand-history function will be
invoked automatically before the completion attempt, expanding normal csh
history substitutions.
For covert operation, the variable nobeep can be set; it will prevent the
completion mechanism, as well as tcsh in general, from actually beeping.
Finally, if the autocorrect variable is set, the spelling correction is
attempted for any path components up to the completion point.
5. LISTING OF POSSIBLE NAMES
At any point in typing a command, you may request "what names are
available". Thus, when you have typed, perhaps:
> cd ~speech/data/fritz/
you may wish to know what files or sub-directories exist (in
~speech/data/fritz), without, of course, aborting the command you are
typing. Typing the character Control-D (^D), will list the names (files,
in this case) available. The files are listed in multicolumn format,
sorted column-wise. Directories are indicated with a trailing `/',
executable files with a `*', symbolic links with a '@', sockets with a
'=', FIFOs (named pipes) with a '|', character devices with a '%', and
block devices with a '#'. Once printed, the command is re-echoed for you
to complete.
Additionally, one may want to know which files match a prefix. If the
user had typed:
> cd ~speech/data/fr[^D]
all files and sub-directories whose prefix was ``fr'' would be printed.
Notice that the example before was simply a degenerate case of this with
a null trailing file name. (The null string is a prefix of all strings.)
Notice also, that a trailing slash is required to pass to a new directory
for both file name completion and listing.
The degenerate
> ~[^D]
will print a full list of login names on the current system. Note,
however, that the degenerate
> [^D]
does not list all of the commands, but only the files in the current
working directory.
Listing/expanding of words that match a name containing wildcard
characters can be done via the list-glob/expand-glob function:
> ls
foo.c bar.c a.out
> vi *.c[^Xg]
foo.c bar.c
> vi *.c[^X*]
> vi foo.c bar.c
Command Name Recognition
Command name recognition and completion works in the same manner as file
name recognition and completion above. The current value of the
environment variable PATH is used in searching for the command. For
example
> newa[TAB]
might expand to
> newaliases
Also,
> new[^D]
would list all commands (along PATH) that begin with "new".
Note that Control-D has three different effects on tcsh. On an empty line
(one that contains nothing, not even spaces), ^D sends an EOF to tcsh
just as it does for normal programs. When the cursor is in the middle of
a line of text, ^D deletes the character that the cursor is under.
Finally, a ^D at the end of a line of text lists the available names at
that point. To get a list of available names when the cursor is in the
middle of a line (or on an empty line), a Meta-Control-D should be typed
(Escape followed by Control-D).
6. SPELLING CORRECTION
If while typing a command, the user mistypes or misspells a file name,
user name, or command name, tcsh can correct the spelling. When
correcting a file name, each part of the path is individually checked and
corrected. Spelling correction can be invoked in several different ways:
The spell-word function, normally bound to M-s (and M-S), will attempt to
correct the word immediately before the cursor. For example, suppose
that the user has typed:
> cd /uxr/spol/news[ESC s]
Tcsh will check the path for spelling, correct the mistakes, and redraw
the line as
> cd /usr/spool/news
leaving the cursor at the end of the line.
Spelling correction of the entire command line (independent of where the
cursor is) can be done with the spell-line function, normally bound to
M-$ (Escape Dollar-sign). It will check each word independently, but in
order to avoid e.g. command options, no correction is attempted on words
whose first character is found in the string "!.\^-*%".
Finally, automatic spelling correction will be done each time the Return
key is hit, if the correct variable is set to an appropriate value:
correct=cmd will cause the spelling of the command name only to be
checked, while correct=all causes checking of all words on the line, like
the spell-line function. If any part of the command line is corrected,
the user will be given a special prompt as defined by the prompt3
variable, followed by the corrected line, e.g.
> lz /usr/bin
CORRECT>ls /usr/bin (y|n|e)?
Answering 'y' or at the prompt will cause the corrected line to
be executed, 'e' will leave the uncorrected command in the input buffer
and anything else will execute the original line unchanged.
Automatic correction is not guaranteed to work the way the user intended.
Command line parsing is done in a rudimentary fashion. It is mostly
provided as an experimental feature. Suggestions and improvements are
welcome.
7. DOCUMENTATION LOOKUP
The editor function run-help (M-h) prints a help file on the current
command (using the same definition of current as the completion routines
use). This help file is found by searching the path list HPATH for files
of the form foo.help, foo.1, foo.8, or foo.6 in that order (assuming that
the current command is foo). The file is just printed, not paged in any
way. This is because run-help is meant to be used to look up short help
files, not manual pages (although it can do manual pages also).
8. ENHANCED HISTORY MECHANISM
Tcsh will save the history list between login sessions. It does this by
writing the current list to the file "~/.history" on logout, and reading
it in on login. For example, placing the line
> set history=25 savehist=20
tells tcsh to save the last 25 commands on the history list, and to save
the last 20 of them between logins. The "savehist" variable may be set
up to the size of history, although it is an error to have savehist
larger than history. In addition to the above tcsh, keeps unparsed
(literal) versions of the history if the variable histlit is set. Also
the toggle-history function toggles between the parsed and literal
version of the recalled history in the editor buffer. For example:
> set histlit
> echo !:s/foo/bar; ls
Modifier failed.
> ^P
> echo !:s/foo/bar; ls
> unset histlit
> echo !:s/foo/bar; ls
Modifier failed.
> ^P
> echo unset histlit[M-r]
> echo !:s/foo/bar; ls
Tcsh also supports the history escape !#. This undocumented csh escape
holds the words of the current line. This is useful in renaming commands:
> mv foo bar!#:1
mv foo barfoo
Care should be taken when using this history expansion in csh since there
is no check for recursion. In tcsh up to 10 levels of recursion are
allowed.
Another difference between tcsh and csh history expansion, is the
treatment of history arguments. In csh !3d expands to event 3 with the
letter "d" appended to it. There is no way to repeat a command that
begins with a number using the name of the command in the history escape.
In tcsh only numeric arguments are treated as event numbers; therefore
!3d is interpreted as: repeat the last command that started with the
string "3d". To mimic the csh behavior !3\d can be used.
9. AUTOMATIC LOGOUT/LOCKING
The automatic locking and logout time are controlled by the variable
autologout. The value of the first word is the number of minutes of
inactivity will be allowed before automatically logging the user out.
When that many minutes have been reached, the shell prints "auto-logout"
and dies (without executing ~/.logout). The default for tcsh is to set
autologout for 60 minutes on login shells, and when the user is root. To
disable autologout (for instance in a window system), unset the shell
variable autologout.
The value of the optional second word indicates the number of minutes of
inactivity after which the user will be prompted for his login password
to continue working. Failure to enter the correct password 5 times,
results in auto-logout.
10. EXECUTION OF A COMMAND PRIOR TO EACH PROMPT
Tcsh supports a special alias, precmd, which if set holds a command that
will be executed before printing each prompt. For example, if the user
has done
> alias precmd date
then the program date will be run just before the shell prompts for each
command. There are no limitations on what precmd can be set to do,
although discretion should be used.
11. PERIODIC COMMAND EXECUTION
Tcsh is now capable of providing periodic command execution through the
use of the shell variable tperiod and the alias periodic. When these
items are set, the alias periodic will be executed every tperiod minutes.
This provides a convenient means for checking on common but infrequent
changes, such as new messages. Example:
> set tperiod = 30
> alias periodic checknews
This will cause the checknews(1) program to be run every 30 minutes.
Having the alias periodic set but with an unset tperiod (or a value of 0
for tperiod) will cause periodic to degenerate to another form of precmd.
12. NEW PROMPT FORMAT
The format for the prompt shell variable has been changed to include many
new things, such as the current time of day, current working directory,
etc. The new format uses "%" to signal an expansion, much like
printf(3S). The available sequences are:
%/ Current working directory.
%~ cwd. If it starts with $HOME, that part is
replaced by a ~. In addition if a directory
name prefix matches a user's home directory,
that part of the directory will be substituted
with ~user. NOTE: The ~user substitution will
only happen if the shell has performed a ~
expansion for that user name in this session.
%c or %. Trailing component of cwd, may be
followed by a digit to get more than one
component, if it starts with $HOME, that
part is replaced with a ~.
%C Trailing component of cwd, may be followed
by a digit to get more than one component, no
~ substitution.
%h, %!, ! Current history event number.
%M The full machine hostname.
%m The hostname up to the first ".".
%S (%s) Start (stop) standout mode.
%B (%b) Start (stop) boldfacing mode. (Only if
tcsh was compiled to be eight bit clean.)
%U (%u) Start (stop) underline mode. (Only if
tcsh was compiled to be eight bit clean.)
%t or %@ Current time of day, in 12-hour, am/pm format.
%T Current time of day, in 24-hour format.
(But see the ampm shell variable below.)
%p Current time in 12-hour format, am/pm format with seconds.
%P Current time in 24-hour format, with seconds.
\c `c' is parsed the same way as in bindkey.
^c `c' is parsed the same way as in bindkey.
%% A single %.
%n The user name, contents of $user.
%d The weekday in format.
%D The day in dd format.
%w The month in format.
%W The month in mm format.
%y The year in yy format.
%Y The year in yyyy format.
%l The line (tty) the user is logged on.
%L clear from prompt to end of display or end of line.
%# A `#' if tcsh is run as a root shell,
a `>' if not.
%{..%} Include string as a literal escape sequence.
Note that the enclosed escape sequence, should
only be used to change terminal attributes and
should not move the cursor location. Also, this
cannot be the last character in the prompt
string. (Available only if tcsh was compiled to
be eight bit clean.)
%? return code of the last command executed just
before the prompt.
%R In prompt3 this is the corrected string; in
prompt2 it is the status of the parser.
On %C, %c and %., if the optional digit is 0, then the next digit is
interpreted as the number of directory components to be skipped, and the
number of components skipped are reported as: /path/path.
The sequences for standout are often used to indicate that this is an
enabled (running as root) shell. An example:
> set prompt="%m [%h] %U[%@]%u [%/] you rang? "
tut [37] [2:54pm] [/usr/accts/sys] you rang? _
In addition, there is a new variable, prompt2, which is used to prompt
for the body of while and for loops (wherever normal csh prompts with a
question mark). The default for prompt2 is "%R? ": the status of the
parser followed by a question mark. This alternate prompt is also used
when the parser is waiting for more input; i.e. when the previous line
ended in a \. The prompt3 variable is used when displaying the corrected
command line when automatic spelling correction is in effect; it defaults
to "CORRECT>%R (y|n|e)? ".
13. TIME-STAMPED HISTORY LIST
The history list in tcsh now has a time-of-day stamp attached to each
history list event. This time stamp is printed whenever the history
command is executed. This allows the user to keep track of when the
various events occurred. The time stamps are not maintained on the saved
history list (also available in csh); thus, on logging back in, all the
saved history events will be recorded with the login time as their time
stamp. The time stamp printouts can be omitted from the history list by
adding the -t switch to the history command. Tcsh provides a way to
save, restore and clear the history list in a file.
history -S []
history -L []
history -c
The 'S' flag saves the current history, the 'L' flags loads the history,
and the 'c' flag clears the history. If a filename is not specified,
then $HOME/.history is used.
14. DIRECTORY ACCESS
Tcsh supports three new flags to control directory style printing for cd,
pushd, popd, and dirs:
-n Print entries in new lines so that the screen width is not exceeded
-l Don't print ~ but print the whole path
-v Print the stack entries one in each line, preceded by the stack
number.
Note that popd +n can be used to pop out stack entries of directories
that do not exist any more.
Tcsh always saves the last directory visited. Changing to the previous
directory can be done by using 'cd -' or 'pushd -'.
Tcsh will now allow the user to access all elements in the directory
stack directly. The syntax "=" is recognized by tcsh as
indicating a particular directory in the stack. (This works for the
file/command name recognition as well.) This syntax is analogous to the
~ syntax for access to users' home directories. The stack is viewed as
zero-based, i.e., =0 is the same as $cwd, which is the same as ".". As a
special case, the string "=-" is recognized as indicating the last
directory in the stack. Thus,
> dirs -v
0 /usr/net/bin
1 /usr/spool/uucp
2 /usr/accts/sys
> echo =2
/usr/accts/sys
> ls -l =1/LOGFILE
-rw-r--r-- 1 uucp 2594 Jan 19 09:09 /usr/spool/uucp/LOGFILE
> echo =-/.cs*
/usr/accts/sys/.cshrc
> echo =4
Not that many dir stack entries.
>
Tcsh will complain if you ask for a directory stack item which does not
exist.
In the normal csh, saying "pushd +2" would rotate the entire stack around
through 2 stack elements, placing the entry found there at the top of the
stack. If, however, the new shell variable dextract is set, then issuing
"pushd +n" will cause the nth directory stack element to be extracted
from its current position, which will then be pushed onto the top of the
stack. Example:
> dirs
~ /usr/spool/uucp /usr/net/bin /sys/src
> set dextract
> pushd +2
/usr/net/bin ~ /usr/spool/uucp /sys/src
> unset dextract
> pushd +2
/usr/spool/uucp /sys/src /usr/net/bin ~
Tcsh provides a way to save, restore and clear the directory stack in a
file.
dirs -S []
dirs -L []
dirs -c
The 'S' flag saves the current directory stack, the 'L' flags loads the
directory stack, and the 'c' flag clears the directory stack. If a
filename is not specified, then $HOME/.cshdirs is used.
In addition, if the shell variable dunique is set, only directories that
are not already in the directory stack will be added when push is
invoked.
The way symbolic links that point to directories are crossed is
determined by the symlinks variable. By default, it is not set to
anything and symbolic links are not treated specially. However, it can be
set to either: chase, ignore, or expand. If symlinks is set to chase,
then every time the directory changes, $cwd reflects the real directory
name, and not the name through the link. A notable exception is the
user's home directory, but that should be fixed. If symlinks is set to
either ignore or expand, then tcsh tries to determine the current
directory name relative to the name of the current directory before the
link was crossed. In simple terms, if you chdir through a symbolic link
and then cd .., you will end .. relatively to where you were before you
crossed the link and not .. relatively to where the symbolic link points.
While ignore affects only builtin commands and completion, expand affects
command execution too, by `fixing' arguments that it considers to be path
names. Unfortunately this does not work in every case, specially when
file arguments are embedded in command line options. Expand also allows
to specify the `real' (as opposed to the one determined relatively to
$cwd), by quoting the file argument.
For example:
> cd /tmp
> mkdir from from/src to
> ln -s ../from/src to/dst
> unset symlinks
> cd /tmp/to/dst; echo $cwd
/tmp/to/dst
> cd ..; echo $cwd
/tmp/from
> set symlinks=chase
> cd /tmp/to/dst; echo $cwd
/tmp/from/src
> cd ..; echo $cwd
/tmp/from
> set symlinks=ignore
> cd /tmp/to/dst; echo $cwd
/tmp/to/dst
> cd ..; echo $cwd
/tmp/to
> set symlinks=expand
> cd /tmp/to/dst; echo $cwd
/tmp/to/dst
> cd ..; echo $cwd # builtin
/tmp/to
> cd /tmp/to/dst; echo $cwd
/tmp/to/dst
> cd ".."; echo $cwd # quoted
/tmp/from
> /bin/echo .. # rewrites non builtin commands.
/tmp/to
> /bin/echo ".."
While the expand setting is the most convenient, and makes symbolic links
invisible, it can sometimes be misleading and confusing in cases where it
fails to recognize arguments. A compromise is to use the ignore setting
and use the editor functions "normalize-path", bound by default to ^Xn.
15. WATCHING FOR LOGINS AND LOGOUTS
Tcsh has a mechanism so that the user can watch for login and logout
activity of any user or terminal in the system. This is accomplished
using the new special shell variable watch, which contains login/terminal
pattern pairs to be checked for activity. For example:
> set watch=(sys ttyjd root console)
This setting will allow the user to check on when the user "sys" logs in
on /dev/ttyjd. Similarly, it will inform the user of root's activity on
the console. In order to be more general, the word "any" may be
substituted for either a user's or a terminal's name, thus allowing
> set watch=('b*' any any ttyh0)
which will check for users that match the pattern 'b*' logging in or out
of the system on any terminal, as well as anyone logging in to
/dev/ttyh0. Naturally, the completely general case
> set watch=(any any)
allows the user to check on any and all login/logout activity in the
system.
By default, the interval between checks of users on the system is 10
minutes; this can be changed by making the first element of watch a
number of minutes which should be used instead, as in
> set watch=(40 any any)
which will check for any users logging in or out every 40 minutes.
There is also a new command, log, which is used to cause tcsh to inform
the user of all users/terminals affected by watch whether they have been
announced before or not. This is useful if a user has been on for some
time and cannot remember if a particular person/terminal is online right
now or not. Log will reset all indication of previous announcement and
give the user the login list all over again, as well as printing the
current value of watch.
The first time that watch is set at tcsh startup, all affected users and
terminals will be printed as though those users/terminals had just logged
on. This may appear to be a bug, but is generally considered a feature,
since it allows the user to see who is on when he first logs in.
The format of the printouts can be tailored via setting of the variable
who. In addition to the standard prompt % escapes, the following
sequences are available for the format specification:
%n The name of the user that logged in/out.
%a The observed action, i.e. "logged on",
"logged off", or "replaced on".
%l The line (tty) the user is logged on.
%M The full hostname of the remote host ("local"
if non-remote).
%m The hostname up to the first ".". If only
the ip address is available or the utmp
field contains the name of an x-windows
display, the whole name is printed.
The %M and %m sequences are only available on systems that store the
remote hostname in /var/adm/utmp. If who is not set, the format defaults
to "%n has %a %l from %m.", or "%n has %a %l." on systems that don't
store the hostname.
16. TIMED EVENT LIST
Tcsh now supports a scheduled-event list through the use of the command
sched. This command gives the user a mechanism by which to arrange for
other commands to be executed at given times. An event is added to the
scheduled-event list by saying
> sched [+]hh:mm
as in
> sched 11:00 echo It\'s eleven o\'clock.
This will make an entry in the list at 11am for the echo command to be
run with the given arguments. The time may be specified in either
absolute or relative time, and absolute times may have a
morning/afternoon specification as well, using "am" or "pm." For
example,
> sched +2:15 /usr/lib/uucp/uucico -r1 -sother
> sched 5pm set prompt='[%h] It\'s after 5; go home: >'
> sched +3am echo This syntax doesn\'t work.
Relative time inconsistent with am/pm.
>
Note that tcsh will complain if you try to make faulty time
specifications.
Printing the current time-event list is accomplished by giving the sched
command with no arguments:
> sched
1 Wed Apr 4 15:42 /usr/lib/uucp/uucico -r1 -sother
2 Wed Apr 4 17:00 set prompt=[%h] It's after 5; go home: >
>
There is also a mechanism by which the user can remove an item from the
list:
> sched --3
Usage for delete: sched .
> sched -3
Not that many scheduled events.
> sched -2
> sched
1 Wed Apr 4 15:42 /usr/lib/uucp/uucico -r1 -sother
>
All commands specified on the scheduled-event list will be executed just
prior to printing the first prompt immediately following the time when
the command is to be run. Hence, it is possible to miss the exact time
when the command is to be run, but tcsh will definitely get around to all
commands which are overdue at its next prompt. Scheduled-event list
items which come due while tcsh is waiting for user input will be
executed immediately. In no case, however, will normal operation of
already-running commands be interrupted so that a scheduled-event list
element may be run.
This mechanism is similar to, but not the same as, the at(1) command on
some Unix systems. Its major disadvantage is that it does not
necessarily run a command at exactly the specified time (but only if
another command is already being run). Its major advantage is that
commands which run directly from tcsh, as sched commands are, have access
to shell variables and other structures. This provides a mechanism for
changing one's working environment based on the time of day.
17. BUILTIN FOR ls -F
There is a new builtin command called ls-F which does the same thing as
the command "ls -F". If the shell variable showdots has been set, it
acts like "ls -aF". If showdots is equal to "-A", then ls-F acts like "ls
-AF". Ls-F works like ls, only it is generally faster, since it does not
need to fork and exec, and safer against Trojan horses if the user has
`.' in the execution path. If other switches are passed to ls-F, then the
normal ls is executed. Aliasing ls to ls-F provides a fast alternative
way of listing files. Note that on non BSD machines, where ls -C is not
the default, ls-F, behaves like ls -CF.
ls-F appends the following characters depending on the file type:
= File is an AF_UNIX domain socket.
[if system supports sockets]
| File is a named pipe (fifo)
[if system supports named pipes]
% File is a character device
# File is a block device
/ File is a directory
* File is executable
+ File is a hidden directory [aix]
or context dependent [hpux]
: File is network special [hpux]
On systems that support symbolic links the variable listlinks controls
the way symbolic links are identified. If listlinks is not set then the
character '@' is appended to the file. If listlinks is set then the
following characters are appended to the filename depending on the type
of file the symbolic links points to:
@ File is a symbolic link pointing
to a non-directory
> File is a symbolic link pointing
to a directory
& File is a symbolic link pointing
to nowhere
While setting listlinks can be helpful while navigating around the file
system, it slows down ls-F and it causes mounting of file systems if the
symbolic links point to an NFS auto-mounted partition.
18. GLOBBING SYNTAX ADDITIONS
The syntax for any character in a range (for example ".[a-z]*") has been
extended so as to conform with standard Unix regular expression syntax
(see ed(1)). Specifically, after an open bracket ("["), if the first
character is a caret ("^") then the character matched will be any not in
the range specified. For example:
> cd ~
> echo .[a-z]*
.cshrc .emacs .login .logout .menuwmrc
> echo .[^.]*
.Xdefaults .Xinit .cshrc .emacs .login .logout .menuwmrc
>
Note that the second form includes .Xdefaults and .Xinit because 'X' (and
all the lower case letters) are outside of the range of a single '.'.
Also the ability to negate a globbing pattern has been added:
> echo *
foo foobar bar barfoo
> echo ^foo*
bar barfoo
Note that this does not work correctly if the expression does not have
any wildcard characters (?*[]) or if the expression has braces {}.
Currently, \< and \> are not supported.
19. NEW ENVIRONMENT AND SHELL VARIABLES
On startup, tcsh now automatically initializes the environment variable
HOST to the name of the machine that it is running on. It does this by
doing a gethostname(2) system call, and setting HOST to the result.
Tcsh also initializes the environment variable HOSTTYPE to a symbolic
name for the type of computer that it is running on. This is useful when
sharing a single physical directory between several types of machines
(running NFS, for instance). For example, if the following is in .login:
set path = (~/bin.$HOSTTYPE /usr/ucb /bin /usr/bin /usr/games .)
and the user has directories named "bin.machine" (where machine is a name
from the list below), then the user can have the same programs compiled
for different machines in the appropriate "bin.machine" directories and
tcsh will run the binary for the correct machine.
The current possible values are:
386BSD an Intel 386, running 386BSD
aix370 an IBM 370, running aix
aixESA an IBM ESA, running aix
alliant an Alliant FX series
alliant-fx80 an Alliant FX80 (mc68000 based)
alliant-fx2800 an Alliant FX2800 (i860 based)
alpha an DEC Alpha running OSF/1
amdahl an Amdahl running uts 2.1
amiga an amiga running amix 2.02
apollo an Apollo running DomainOS
att3b15 an AT&T 3b15
att3b2 an AT&T 3b2
att3b20 an AT&T 3b20
att3b5 an AT&T 3b5
balance a Sequent Balance (32000 based)
bsd386 an Intel 386, running BSDI's bsd386
butterfly a BBN Computer Butterfly 1000
coh386 a 386 running Coherent 4.0
coherent an unknown machine running Coherent
convex a Convex
cray a Cray running Unicos
decstation a DecStation XXXX
eta10 an ETA 10 running SVR3
gould-np1 a Gould NP1
hk68 a Heurikon HK68 running Uniplus+ 5.0
hp300 an HP 9000, series 300, running mtXinu
hp800 an HP 9000, series 800, running mtXinu
hp9000s300 an HP 9000, series 300, running hpux
hp9000s500 an HP 9000, series 500, running hpux
hp9000s700 an HP 9000, series 700, running hpux
hp9000s800 an HP 9000, series 800, running hpux
hp an HP, running hpux
i386 an Intel 386, generic
i386-mach an Intel 386, running mach
i386-linux an Intel 386, running Linux
i386-emx an Intel 386, running emx [unix emulation under OS/2]
intel386 an Intel 386, running INTEL's SVR3
iris3d a Silicon Graphics Iris 3000
iris4d a Silicon Graphics Iris 4D
isc386 an Intel 386, running ISC
lynxos-i386 An Intel 386 running Lynx/OS-2.1
lynxos-i860 An Intel 860 running Lynx/OS-2.1
lynxos-m68k A Motorola 68K running Lynx/OS-2.1
lynxos-m88k A Motorola 88K running Lynx/OS-2.1
lynxos-sparc A sparc running Lynx/OS-2.1
lynxos-mips A mips running Lynx/OS-2.1
lynxos-unknown Something running Lynx/OS-2.1
m88k an mc88000 CPU machine
mac2 an Apple Computer Macintosh II, running AUX
masscomp a Concurrent (Masscomp), running RTU
minix386 an i386 running minix
minix a mac or an amiga running minix
mips another mips CPU
multimax an Encore Computer Corp. Multimax (32000 based)
news a Sony NEWS 800 or 1700 workstation
news_mips a NeWS machine with mips CPU
nd500 a Norsk Data ND 500/5000 running Ndix
ns32000 an NS32000 CPU machine
next a NeXT computer
paragon an intel paragon running osf1
pfa50 a PFU/Fujitsu A-xx computer
ps2 an IBM PS/2, running aix
ptx a Sequent Symmetry running DYNIX/ptx (386/486 based)
pyramid a Pyramid Technology computer (of any flavor)
rs6000 an IBM RS6000, running aix
rt an IBM PC/RT, running BSD (AOS 4.3) or mach
rtpc an IBM PC/RT, running aix
sco386 an Intel 386, running SCO
stellar a stellar running stellix
sun a Sun workstation of none of the above types
sun2 a Sun Microsystems series 2 workstation (68010 based)
sun3 a Sun Microsystems series 3 workstation (68020 based)
sun386i a Sun Microsystems 386i workstation (386 based)
sun4 a Sun Microsystems series 4 workstation (SPARC based)
symmetry a Sequent Symmetry running DYNIX 3 (386/486 based)
sysV88 a Motorola MPC running System V/88 R32V2 (SVR3/88100 based)
tahoe a tahoe running 4BSD
tek4300 a Tektronix 4300 running UTek (BSD 4.2 / 68020 based)
tekXD88 a Tektronix XD88/10 running UTekV 3.2e (SVR3/88100 based)
titan an Stardent Titan
unixpc an UNIX/PC running SVR1 att7300 aka att3b1
vax a Digital Equipment Corp. Vax (of any flavor)
vistra800 a Stardent Vistra 800 running SVR4
VMS-POSIX a vax? running VMS/POSIX
(The names of the machines are usually trade marks of the corresponding
companies.)
Tcsh also initializes the shell variables uid and gid to the value of the
current real user ID/GID. This is useful for telling what user/group the
shell is running as. Under Domain/OS tcsh will also set oid indicating
the current real organization id.
20. COMMANDS FOR DEBUGGING
Only two such commands are available at this point, both concerned with
testing termcap entries.
telltc tells you, politely, what tcsh thinks of your terminal, and settc
`cap' `value' tells tcsh to believe that the termcap capability `cap' (
as defined in termcap(5) ) has the value `value'. No checking for sanity
is performed, so beware of improper use.
Note that Concept terminal users may have to "settc xn no" to get proper
wrapping at the rightmost column.
21. SEARCHING FOR THE VISUAL HISTORY
Four new editor functions have been added in emacs mode: Two of them,
history-search-backward, bound to M-p (and M-P), and history-search-
forward, bound to M-n (and M-N), implement a conventional search
mechanism, while the other two, i-search-back and i-search-fwd, both
unbound by default, implement the emacs-style incremental search.
History-search-backward (history-search-forward) searches backward
(forward) through the history list for previous (next) occurrence of the
beginning of the input buffer as a command. That is, if the user types:
> echo foo
foo
> ls
filea fileb
> echo bar
bar
>
and then types "echop", the shell will place "echo bar" in the
editing buffer. If another M-p was entered, the editing buffer would
change to "echo foo". This capability is compatible with the plain
visual history; if the user were to then enter ^P the editing buffer
would be changed to "ls". The pattern used to search through the history
is defined by the characters from the beginning of the line up to the
current cursor position and may contain a shell globbing pattern.
Successive history searches use the same pattern.
When the incremental search functions are used, a prompt - "bck:" or
"fwd:", depending on the chosen direction - appears, and characters typed
are appended to the search pattern. The matching command line is placed
in the editing buffer, with the cursor positioned at the point where the
pattern was found (the incremental search will also do searching within a
command line). If the search fails, the terminal bell is rung, and the
':' in the prompt is changed to '?'.
If these functions are bound to single characters, and one of those is
typed again during the incremental search, the search continues in the
corresponding direction, with the pattern unchanged; if the previous
search failed, this will also cause it to "wrap around" the history list.
Finally, the following characters also have a special meaning during the
search:
Delete (or any character bound to backward-delete-char)
Undo the effect of the last character typed,
deleting a character from the pattern if appropriate.
^G Abort the search, back to the last successful one
if previous search failed, otherwise entire search.
^W Append the rest of the current word to the pattern.
ESC Terminate the search, leaving current line in buffer.
Any other character, that isn't bound to self-insert-command, terminates
the search, leaving the current command line in the editing buffer, after
which tcsh interprets the character as if it was normal input - notably
Return will cause the current command line to be executed.
In vi mode "vi-search-fwd" (bound to '/') and "vi-search-back" (bound to
'?') can be used to search the visual history. In command mode '/' or '?'
followed by a shell pattern, searches the visual history for the pattern.
The pattern can be terminated either with a Return, in which case the
matched history event is placed in the command buffer or an Escape, in
which case the matched history event is executed. If no history event
matches the shell pattern then the bell is rung.
22. BUILTIN WHICH(1)/WHERE COMMANDS
There is now a builtin version of the which(1) command. The builtin
version is just like the original, except that it correctly reports
aliases peculiar to this tcsh, and builtin commands. The only other
difference is that the builtin runs somewhere between 10 and 100 times
faster. There is also a key-function interface to this command: the
which-command function (normally bound to M-?), can be used anywhere on
the command line, and will in effect do a 'which' on the command name.
Similarly where will report all known instances of the command: aliases,
builtins, as well as all references in the path.
23. RESTARTING A STOPPED EDITOR
There is another new editor function: run-fg-editor, which is bound to
M-^Z. When typed, it saves away the current input buffer, and looks for
a stopped job with a name equal to the sl="`echotc fs`"
> echo -n "$tosl";date; echo -n "$frsl"
Echotc accepts two flags. The flag -v enables verbose messages and the
flag -s ignores any errors and returns the empty string if the capability
is not found.
25. EXECUTION OF A COMMAND AFTER CHANGING THE CURRENT WORKING DIRECTORY
Tcsh now supports a special alias, cwdcmd, which if set holds a command
that will be executed after changing the value of $cwd. For example, if
the user is running on an X window system xterm(1), and a re-parenting
window manager that supports title bars such as twm(1) and has done:
> alias cwdcmd 'echo -n "^[]2;${HOST}:$cwd ^G"'
then the shell will change the title of the running xterm(1) to be the
name of the host, a colon, and the full current working directory. A more
fancy way to do that is:
> alias cwdcmd 'echo -n "^[]2;${HOST}:$cwd^G^[]1;${HOST}^G"'
This will put the hostname and working directory on the title bar but
only the hostname in the icon manager menu. Note that if a user defines
cwdcmd to contain a cd, pushd, or popd, command, an infinite loop may
result. In this case, it is the author's opinion that said user will get
what he deserves.
26. NATIVE LANGUAGE SYSTEM
Tcsh is eight bit clean (if so compiled, see the description of the
version shell variable below), and will thus support character sets
needing this capability. The tcsh support for NLS differs depending on
whether it was compiled to use the system's NLS (again, see the version
variable) or not. In either case, the default for character
classification (i.e. which characters are printable, etc.) and sorting is
7-bit ascii, and any setting or unsetting of the LANG or LC_CTYPE
environment variables will cause a check for possible changes in these
respects.
When using the system's NLS, the setlocale C library function will be
called to determine appropriate character classification and sorting -
this function will typically examine the LANG and LC_CTYPE variables for
this purpose (refer to the system documentation for further details).
Otherwise, NLS will be simulated, by assuming that the ISO 8859-1
character set is used whenever either of the LANG and LC_CTYPE variables
are set, regardless of their values. Sorting is not affected for the
simulated NLS.
In addition, with both real and simulated NLS, all printable characters
in the range \200-\377, i.e. those that have M- bindings, are
automatically rebound to self-insert-command (the corresponding binding
for the escape+ sequence, if any, is left alone). This automatic
rebinding is inhibited if the NOREBIND environment variable is set - this
may be useful for the simulated NLS, or a primitive real NLS which
assumes full ISO 8859-1 (otherwise all M- bindings in the range
\240-\377 will effectively be undone in these cases). Explicitly
rebinding the relevant keys, using bindkey, is of course still possible.
Unknown characters (i.e. those that are neither printable nor control
characters) will be printed using the \nnn format. If the tty is not in
8 bit mode, other 8 bit characters will be printed by converting them to
ascii and using standout mode. Tcsh will never change the 7/8 bit mode
of the tty, and will track user-initiated settings for this - i.e. it may
be necessary for NLS users (or, for that matter, those that want to use a
Meta key) to explicitly set the tty in 8 bit mode through the appropriate
stty(1) command in e.g. the .login file.
27. AUTOMATIC PROCESS TIME REPORTING
Automatic process time reporting is a feature that exists in csh, but it
is usually not documented. In addition tcsh provides a slightly enriched
syntax. Process time reports are controlled via the time shell variable.
The first word of the time variable indicates the minimum number of CPU
seconds the process has to consume before a time report is produced. The
optional second word controls the format of the report. The following
sequences are available for the format specification:
%U The time the process spent in user mode
in cpu seconds.
%S The time the process spent in kernel mode
in cpu seconds.
%E The elapsed time in seconds.
%P The CPU percentage computed as (%U + %S) / %E.
The following sequences are supported only in systems that have the BSD
resource limit functions.
%W Number of times the process was swapped.
%X The average amount in (shared) text space used
in Kbytes.
%D The average amount in (unshared) data/stack
space used in Kbytes.
%K The total space used (%X + %D) in Kbytes.
%M The maximum memory the process had in use at
any time in Kbytes.
%F The number of major page faults (page needed to
be brought from disk).
%R The number of minor page faults.
%I The number of input operations.
%O The number of output operations.
%r The number of socket messages received.
%s The number of socket messages sent.
%k The number of signals received.
%w Number of voluntary context switches (waits).
%c Number of involuntary context switches.
The default time format is "%Uu %Ss %E %P %X+%Dk %I+%Oio %Fpf+%Ww" for
systems that support resource usage reporting and "%Uu %Ss %E %P" for
systems that do not.
For Sequent's DYNIX/ptx %X, %D, %K, %r and %s are not supported.
However, the following additional sequences are available.
%Y The number of system calls performed.
%Z The number of pages which are zero-filled
on demand.
%i The number of times a process' resident
set size was increased by the kernel.
%d The number of times a process' resident
set size was decreased by the kernel.
%l The number of read system calls performed.
%m The number of write system calls performed.
%p the number of reads from raw disk devices.
%q the number of writes to raw disk devices.
The default time format for Sequent's DYNIX/ptx is "%Uu %Ss $E %P %I+%Oio
%Fpf+%Ww". Also note that the CPU percentage can be higher than 100% on
multi-processors.
28. OS/DEPENDENT BUILTIN SUPPORT
TRANSPARENT COMPUTING FACILITY
On systems that support TCF (aix-ibm370, aix-ps2) the following builtins
have been added:
getspath Print the current system execution path.
setspath LOCAL|| ...
Set the current execution path.
getxvers Print the current experimental version prefix.
setxvers []
If the optional string is omitted, any experimental version
prefix is removed. Otherwise the experimental version prefix
is set to string.
migrate [-] |% ...
migrate -
The first form migrates the process or job to the site
specified or the default site determined by the system path.
The second form, is equivalent to 'migrate - $$', i.e.
migrates the current process to the site specified. Note:
migrating tcsh itself can cause unexpected behavior, since the
shell does not like to lose its tty.
In addition, jobs will print the site the job is executing.
Domain/OS Support
inlib ...
Inlib adds shared libraries to the current environment. There is no
way to remove them...
rootnode //
Change the name of the current rootnode. From now on, / will resolve
to //
ver [] []
Without arguments, print $SYSTYPE; with the provided, set
SYSTYPE to the one provided. Valid systypes are bsd4.3 and sys5.3.
If a is argument is given, then is executed
under the specified.
Mach
setpath ...
XXX: What does it do?
Masscomp/RTU
universe ...
Sets the current universe to the specified parameter.
Convex/OS
warp [] ...
Without arguments prints the current value of the universe. With a
universe argument it sets the current universe to the value of the
argument.
29. WINDOW SIZE TRACKING
On systems that support SIGWINCH or SIGWINDOW, tcsh adapts to window
resizing automatically and adjusts the environment variables LINES and
COLUMNS if set. Also if the environment variable TERMCAP contains li#,
and co# fields, these will be adjusted also to reflect the new window
size.
30. INPUT FILES
On startup tcsh will try to source /etc/csh.cshrc and then /etc/csh.login
if the shell is a login shell. Then it will try to source $HOME/.tcshrc
and then $HOME/.cshrc if $HOME/.tcshrc is not found. Then it will source
$HOME/.login if the shell is a login shell. On exit tcsh will source
first /etc/csh.logout and then $HOME/.logout if the shell was a login
shell.
Note: On convexos, stellix and INTEL the names of the system default
files are /etc/cshrc , /etc/login and /etc/logout respectively. On the
NeXT the names are also different: /etc/cshrc.std , /etc/login.std and
/etc/logout.std . Finally, on Irix, A/UX, AMIX, and the Cray, the file
/etc/cshrc is executed instead of /etc/csh.login if the shell is a login
shell.
31. COMMAND LINE OPTIONS
This section describes options that are either undocumented in csh (*) or
present only in tcsh. (+)
-d Force load of directory stack. (+)
-Dname[=value]
Set environment variable name to value. (Domain/OS only) (+)
-F Use fork() instead of vfork() to spawn processes. (Convex/OS only)
(+)
-l Make tcsh behave like a login shell. (+)
-m Allow reading of a .cshrc that does not belong to the effective user.
Newer versions of su(1) can pass that to the shell. (some versions of
csh have it) (+*)
-q Make the shell accept SIGQUIT, and behave when it is used under a
debugger. Job control is disabled. (*)
32. HISTORY AND VARIABLE MODIFIER ENHANCEMENTS
Tcsh accepts more than one variable modifier per variable or history
expansion. For example, in csh(1) the following command expands to:
% set a=/usr/local/foo.bar.baz
% echo $a:t:r:e
foo.bar.baz:r:e
but in tcsh:
> set a=/usr/local/foo.bar.baz
> echo $a:t:r:e
bar
This bug fix changes slightly the input syntax of csh, causing
expressions of the form to have invalid syntax:
> set a=/usr/local/foo.bar.baz
> echo $a:t:$cwd
Unknown variable modifier.
Which is the correct behavior, since after the second colon a variable
modifier is expected and `$' is found. Expressions like this should be
re-written as:
> echo ${a:t}:$cwd
Tcsh can also use the l and u modifiers to change the case of a word.
Also tcsh has an additional : character a which applies the current
modifier multiple times in the same word, in the same way g applies the
modifier once in each word:
> set foo=(a:b:c d:e:f)
> echo $foo:s/:/ /
a b:c d:e:f
> echo $foo:gs/:/ /
a b:c d e:f
> echo $foo:as/:/ /
a b c d:e:f
> echo $foo:ags/:/ /
a b c d e f
The csh expert will notice in the above example another tcsh enhancement.
In csh the s modifier does not work for variables.
The a character works correctly with other modifiers, for example:
> echo $host
tesla.ee.cornell.edu
> echo $host:r
tesla.ee.cornell
> echo $host:ar
tesla
Note: The a character causes a modifier to be applied to a word
repeatedly until the modifier fails. This can lead to an infinite loop in
the current implementation when used with the s modifier. For example
:as/f/ff/ will never terminate. This behavior might change in the future.
33. PROGRAMMABLE COMPLETION
The new complete and uncomplete builtins can change the behavior of the
listing and file-completion in tcsh. For example some commands like cd,
pushd, popd , mkdir(1), rmdir(1) accept only directories as arguments.
Normally tcsh when asked to list or complete an argument for those
commands takes into account all the files and not only directories. This
behavior can be changed by telling tcsh that these commands only expect
directory arguments:
> complete cd 'n/*/d/'
The above command tells tcsh to complete any following word with a
directory.
The syntax for the complete and uncomplete builtins is:
complete [ []]
uncomplete
Completion arguments are matched in turn from left to right and the first
successful match is returned. There are three different completion
arguments, modeled after the sed(1) substitute command and they are of
the form:
///[|/]
The five commands available are:
p This specifies position-dependent completion. The matching pattern
is a numeric range similar to the one used to index shell variables.
If the current word is within that range, then the completion action
is taken. For example:
> complete cd 'p/1/d/'
completes only the first argument of 'cd' with a directory. A
special useful case of position-dependent completion can be used to
disambiguate command completion:
> set autolist
> co[TAB]
complete compress
> complete -co* 'p/0/(complete)/'
> co[TAB]
> complete _
The above command tells the completion mechanism to match any word
on position 0, that matches the pattern co* . If a match is found,
the word is replaced with the literal pattern "complete". The
leading '-' in the pattern signifies that this completion is to be
used only with ambiguous commands.
n,N This command specifies next-word completions. The matching pattern
in this case is a shell pattern that must match the previous word on
the command line (n), or the word before that (N). For example:
> complete find 'n/-user/u/'
Here the argument of the find command which follows the -user
argument is completed from the list of users.
c,C The last two completion commands complete the current word. The
matching pattern in this case must match the prefix of the current
word. For example:
> complete cc 'c/-I/d/'
completes the word containing -I from the list of directories.
While `c' discards the matched prefix, `C' keeps it and applies the
completion using it.
So far the d, u, (word) completion actions have been mentioned. The
complete list of completion actions are:
C Complete completions
S Complete signals
a Complete aliases
b Complete binding
c Complete command
d Complete directory
e Complete environment variable
f Complete file or path component
j Complete jobs
l Complete limits
n Complete nothing
p Complete files using the supplied pathname prefix
s Complete shell variable
t Complete non directory `text' filename
v Complete any variable
u Complete username
x Explain what argument when listing is requested.
$var Complete using words from variable
(...) Complete using words from list
`...` Complete evaluating word list from the output of command.
All the above completion actions, except x, $var, (...), and `...` can
have an additional shell pattern which must match the files to be
completed, separated from the action with a ':'. The 'x' completion
action instead expects the explanation string specified this way. For
example, in the C compiler, it makes sense to complete only files that
the compiler understands:
> complete cc 'n/*/f:*.[cao]/'
It is also useful to exclude files from the completion list. Normally
tcsh will expand the following command:
> set fignore=(.o)
> ls
foo.c foo.o
> vi f[TAB]
> vi foo.c
> rm f[TAB]
> rm foo.c
A better way to do this is to use the complete builtin to protect
precious files:
> complete rm 'n/*/f:^*.{c,h,cc,C,tex,1,man,l,y}/'
> ls
foo.c foo.o
> vi f[TAB]
> vi foo.c
> rm f[TAB]
> rm foo.o
Note that fignore is not used when a shell pattern is specified in a
completion action.
Other commands don't expect files as arguments, so the completion builtin
can be used to change the list of items to be completed:
> complete man 'n/*/c/' # complete commands
> complete which 'n/*/c/'
> complete dbx 'p/2/(core)/' 'n/*/c/'
> complete alias 'p/1/a/' # complete aliases
> complete set 'p/1/s/' # complete variables
> complete finger 'p/1/u/' # complete user-names
Note that in the dbx example, the positional completion is specified
before the next word completion. Since completions are evaluated from
left to right, if the next word completion was specified first it would
always match and the positional completion would never be executed. This
is a common mistake when defining a completion.
In some cases the list needs to be customized or dynamically generated.
> set hostnames=(prep.ai.mit.edu tesla.ee.cornell.edu)
> complete rlogin 'p/1/$hostnames/'
Consider a complex example using matching patterns to direct argument
dependent completions:
> complete find 'n/-fstype/(nfs 4.2)/' 'n/-name/f/' \
'n/-type/(c b d f p l s)/' 'n/-user/u/' 'n/-exec/c/' \
'n/-ok/c/' 'n/-cpio/f/' 'n/-ncpio/f/' 'n/-newer/f/' \
'c/-/(fstype name perm prune type user nouser \
group nogroup size inum atime mtime ctime exec \
ok print ls cpio ncpio newer xdev depth)/' \
'n/*/d/'
The words following the -fstype and -type arguments is to be completed
from the lists specified. The word following the -name, -cpio, -ncpio,
and -newer arguments are to be completed using files or directory
components. The word following the -user argument will be completed from
the list of user names of the system, and the word following the -exec
and -ok arguments will be completed from the list of commands. The
fourth line specifies how the current word will be completed if it starts
with a -. Note that the pattern of this completion argument refers to the
current word and not to the previous word, like before. Finally the last
line in the find completion matches all the remaining cases and requires
a directory component.
> cd /usr
> set autolist
> find [TAB]
bin/ include/ lib/ local/ man/ src/
> find -[TAB]
atime depth group mtime newer ok prune user
cpio exec inum name nogroup perm size xdev
ctime fstype ls ncpio nouser print type
> find -u[TAB]
> find -user [TAB]
christos root
> find -user c[TAB]
> find -user christos
Another useful feature is to override the default suffix rules. A one
chararter suffix can be specified. For example:
> complete rcp 'c/*:/f/' 'p/1/$hosts/:'
> complete finger 'c/*@/$hosts/' 'p/1/u/@'
completes from $hosts appending a `:' and then begins expanding files,
where finger expands user-names appending an `@' and then begins
expanding hosts.
Another exotic example that makes use of dynamic command execution is:
> complete talk p/1/'`users | tr " " "\012" | uniq`'/ \
n/\*/\`who\ \|\ grep\ \$:1\ \|\ awk\ \'\{\ print\ \$2\ \}\'\`/
Here we want to get a list of the active users, as an argument to talk,
then we want to pick the user, and find his tty... Note that there is no
quoting performed inside the completion patterns. If the character '/'
is used in the matched pattern, then another punctuation character can be
used as a separator. The only pattern recognized is $: which is
substituted by the n'th word of the current line.
Notes:
1. The completion command-patterns are overridden when the internal
parsing mechanism determines that the completion is a login name, or
a variable.
2. This is an experimental feature and the syntax/behavior may change
in future versions.
FYI
This shell uses CBREAK mode but takes typed-ahead characters anyway. You
can still use stty(1) to set some of the modes of your terminal (but not
bindings).
This shell will restore your tty to a sane mode if it appears to return
from some command in raw, CBREAK, or noecho mode. This behavior can be
changed using setty.
34. ENHANCED FILE INQUIRIES
Csh allows the following file inquiries that can appear as primitive
operands in expressions. They are for the form -l .
r read access
w write access
x execute access
e existence
o ownership
z zero size
f plain file
d directory
l symbolic link *
Tcsh defines also the following:
c character special file
b block special file
p named pipe (fifo) *
u set-user-ID bit is set
g set-group-ID bit is set
k sticky bit is set
s the file is non-zero size.
t open file descriptor for terminal device [a number]
S socket special file *
X executable in the path or shell builtin
Notes: On systems without the file types indicated by * the file inquiry
operands return false.
If tcsh is compiled for POSIX [i.e. POSIX is defined in config.h], then
the result of test is based on the permission bits of the file and not on
the result of the access(2) system call. I.e. if you mount a file system
read-only, and test -w a file, then the test will succeed in POSIX mode,
if the permissions of the file allow writing.
35. READONLY VARIABLES
Tcsh allows defining variables as readonly. Such variables cannot be
cleared or modified. E.g.
> set -r x=(1 2 3)
> unset x
unset: $x is read-only.
> set x=5
set: $x is read-only.
> set -r x=5
set: $x is read-only.
> echo $x
1 2 3
In addition 'set -r' will list only the readonly variables.
36. IMPLICIT CD
If the variable implicitcd is set, tcsh will treat directory names typed
as commands as though they were requests to change to that directory. If
implicitcd is set to verbose , the change of directory will be echoed to
the output. Implicit cd will not be performed when executing non-
interactive shell scripts, or for command strings of more than one word.
Changing directory has precedence over executing a like-named command,
but is done after any alias substitution. Tilde (~) and variable
expansion works as expected. Some examples:
> set implicitcd = verbose
> ~
cd ~
> pwd
/usr/people/jill
> ..
cd ..
> pwd
/usr/people
> set implicitcd
> /
> pwd
/
> $HOME/work/; pwd
/usr/people/jill/work
> alias games /usr/local/games
> games; pwd
/usr/local/games
There are situations where implicitly changing to a directory as opposed
to executing a like-named command can be dangerous (e.g., being in an
unexpected directory before removing files). For this reason it makes
sense to reflect the current working directory in your prompt string if
you use this feature.
ENVIRONMENT
HPATH -- path to look for command documentation
LANG -- used to give preferred character environment (see NLS)
LC_CTYPE -- used to change only ctype character handling (see NLS)
NOREBIND -- inhibits rebinding of printable characters to self-insert-
command
PATH -- path to look for command execution
SHLVL -- current shell level nesting
TERM -- used to tell how to handle the terminal
LINES -- Number of lines in terminal (see WINDOW SIZE)
COLUMNS -- Number of columns in terminal (see WINDOW SIZE)
TERMCAP -- Terminal capability string (see WINDOW SIZE)
SYSTYPE -- The current system type (Domain OS only)
NEW SHELL VARIABLES
addsuffix add a / for directories, and a space for normal files when
complete matches a name exactly. If unset don't add anything
extra.
ampm show all times in 12 hour, AM/PM format.
autocorrect
Correct mis-spelled path components automatically before
attempting completion.
autoexpand
invoke the expand-history function automatically on completion.
autolist list possibilities on an ambiguous completion.
autologout
The first word indicates number of minutes of inactivity before
automatic logout. The optional second word indicates the
number of minutes of inactivity after which the user will be
prompted for his login password to enter a command.
backslash_quote
makes the backslash quote \, ', and ". This option changes the
parsing mechanism for tcsh, and it can cause syntax errors in
csh scripts.
correct automatically try to correct the spelling of commands. Must be
set to either correct=cmd, only command name will be corrected,
or correct=all, the whole line will be corrected.
dextract extract a directory on pushd rather than rotating.
dirsfile If set, it contains the full path-name where a directory stack
file is read/written. It defaults to $home/.cshdirs. This file
is executed last after .cshrc and .login to restore the
directory stack.
dirstack If set, it contains an array of all the directories on the
directory stack. $dirstack[1] is the current working directory,
$dirstack[2] the first directory on the stack, etc. Setting
$dirstack resets all the stack entries, but the current working
directory which is preserved.
dunique Push only directories that are not already in the directory
stack.
echo_style
Set the style of the builtin echo. Valid values are:
bsd : if the first argument is -n, don't echo a newline.
sysv : recognize \ escape sequences in echo strings.
both : recognize both -n and \ escape sequences.
none : the purist's echo.
edit use the input editor, set by default.
fignore list of file name suffixes (e.g. .o, ~) to ignore during
complete.
gid the current real group id.
histlit If set, history lines in the editor will be shown with its
literal value (that is the line as it was input) instead of the
shells lexical version. The current history line can be toggled
between literal and lexical with the toggle-literal-history
function. History lines saved at shell exit are also saved as
this variable indicates.
histfile If set, it contains the full path-name where a history file is
read/written. It defaults to $home/.history. This is useful
when sharing the same home directory in different machines, or
if one wants to save all the histories in the tty sessions. It
is usually set in .cshrc for interactive shells, because
history is sourced between .cshrc and .login so that it is
available from .login.
history The first word of the history variable indicates the number of
history events to be saved. The optional second word indicates
the format history is printed (Defaults to "%h\t%T\t%R\n").
implicitcd
Can be set to enable implicit cd behavior, or set to verbose to
echo each implicit cd.
inputmode Can be set to either insert or overwrite to control the line
editing behavior, as described in section 1.
listjobs list all jobs when suspending. set listjobs=long, produces long
format.
listlinks Resolve symbolic links when listing files so that the correct
filetype is shown.
listmax maximum number of items to list without asking first.
listmaxrows
maximum number of rows of items to list without asking first.
(local AFEB hack at University of Twente)
matchbeep control beeping on completion. With matchbeep=nomatch,
completion only beeps when there is no match, with
matchbeep=ambiguous, beeps also when there are multiple
matches, with matchbeep=notunique, beeps when there is one
exact and other longer matches, with matchbeep=never, it never
beeps.
nobeep Disables beeping completely.
nokanji If kanji support is enable, setting this variable disables it,
so that the meta key can be used.
nostat An list of directories that should not be stat'ed during a
completion operation. Some directories e.g. "/afs", can take
too much time to complete a stat(2) operation, making them
prime candidates for membership in this list.
oid The organization id number (Domain OS only).
printexitvalue
if an interactive program exits non-zero, print the exit value.
prompt the string to prompt with.
prompt2 the string to prompt for while and for loops with.
prompt3 the string to prompt with when automatic spelling correction
has corrected a command line.
pushdtohome
make pushd with no args do a "pushd ~" (like cd does).
pushdsilent
do not print the dir stack on every pushd and popd.
recexact recognize exact matches even if they are ambiguous.
recognize_only_executables
list choices of commands only displays files in the path that
are executable (slow).
rmstar Prompt the user before execution of `rm *'.
savedirs Before exiting, create a file called $HOME/.cshdirs that
contains the necessary commands to restore the current
directory stack. Tcsh will read this file during startup and
restore t.
tperiod periodic command wait period (in minutes).
tty The name of the tty, or empty if not attached to one.
uid the current real user ID.
version the version ID stamp for this tcsh. It contains, the origin of
this version of tcsh, the date this version was released and a
string containing a comma separated list of the compile time
options enabled:
8b 7b If tcsh was compiled to be eight bit clean
or not. The default is 8b.
nls Set if tcsh uses the system's NLS, should be
the default for systems that have NLS.
lf Set if tcsh should execute .login before
.cshrc on login shells. Default is not set.
dl Set if tcsh should put . last on the path
for security. Default is set.
vi Set if tcsh's default editor is vi. Default
is unset (emacs)
dtr Set if tcsh should drop dtr on login shells
when exiting. Default is unset.
bye Set if tcsh should accept bye in addition
to logout, and rename log to watchlog.
Default is unset.
al Set if tcsh should determine if autologout
should be enabled. The default is set.
kan Set if tcsh is compiled for Kanji.
(ignore the iso character set.) Default is unset.
sm Set if tcsh was compiled to use the system's malloc.
hb Set if tcsh is emulating #! in
shell script execution
In addition to the above strings, administrators can enter local strings
to indicate differences in the local version.
visiblebell
use the visible bell (screen flash) rather than audible bell.
watch list of events to watch.
who format string for the printouts generated when watch is set.
wordchars list of non-alphanumeric characters considered part of a word
for the purpose of the forward-word, backward-word, etc.
functions -- defaults to "*?_-.[]~=".
NEW SPECIAL ALIASES
cwdcmd the command is run after every change of working directory.
periodic the command to be run every tperiod minutes.
precmd the command to be run prior to printing each prompt.
beepcmd the command to be run every time tcsh wants to echo the
terminal bell.
SEE ALSO
xterm(1), twm(1), csh(1), chsh(1), exec(2), exit(2), wait(2), termcap(5),
termio(7)
BUGS
The screen update for lines longer than the screen width is very poor if
the terminal cannot move the cursor up (i.e. terminal type "dumb").
I am certain that there are bugs. Bugs (preferably with fixes) should be
sent to Christos Zoulas (christos@ee.cornell.edu).
LIMITATIONS
In non-interactive mode, signals for Hangup, CPU time limit exceeded and
File size limit exceeded (SIGHUP, SIGXCPU and SIGXFSZ respectively) are
ignored. Also note that the behavior of these signal handlers in
interactive mode is dependent on the way they were handled in the process
from which tcsh was started.
If a user had typed:
> rsh skier@tahoe xwsh -display foo:0
In this case, rsh starts a tcsh (login shell for a user skier on a
machine called tahoe) and passes a command 'xwsh' to be run, the
interactive tcsh in the xwsh will not have these signals enabled. This is
due to the fact that the first tcsh was non-interactive and executes a
'xwsh' command.
If these signals are to be enabled, you can either use csh(1) or first
start an interactive tcsh via rsh and then invoke 'xwsh'.
> rsh skier@tahoe
skier@tahoe 1> xwsh -display foo:0
Sometimes, particularly when using wildcards, the shell will fail to
execute a command, and complain with the message
Arg list too long
This can often be avoided by using multiple commands, the xargs(1)
command, or by increasing the ncargs kernel parameter with the
systune(1m) command.
VERSION
This man page documents tcsh 6.04.00 (Cornell) 93/07/03.
AUTHORS
Ken Greer, HP Labs, 1981
Wrote the command completion.
Mike Ellis, Fairchild, 1983
Added command name recognition/completion.
Paul Placeway, Ohio State CIS dept., 1983
Added the command line editor.
Rayan Zachariassen, University of Toronto, 1984
Added the builtin which feature to the editor, and the code for ls-F .
Also numerous bug fixes, modifications, and performance enhancements.
Chris Kingsley, Caltech
Wrote the fast storage allocator routines (nmalloc.c).
Karl Kleinpaste, CCI 1983-4
Added special aliases, directory stack extraction stuff, login/logout
watch, and scheduled events. Also came up with the idea of the new
prompt format.
Paul Placeway, Ohio State CIS dept., 1987
Re-wrote the editor, cleaned up other code, and added the prompt
routines, added to the syntax for file name expressions, and sped up the
shell some.
Chris Grevstad, TRW, 1987
Ported the 4.3 csh sources to tcsh.
Christos S. Zoulas, Cornell U. EE dept., 1987-92
ported tcsh to HPUX, and System V rel. 2 and 3 and wrote a SysV version
of getwd.c. Added SHORT_STRINGS support. New version of sh.glob.c.
James J Dempsey, BBN, 1988, and Paul Placeway, OSU, 1988
Re-ported tcsh to A/UX.
BUGFIXES AND ENHANCEMENTS
Edward Hutchins, Silicon Graphics Inc., 1996
Added implicit cd.
Tim P. Starrin, National Aeronautics and Space Administration, Langley
Research Center Operations, 1993
Readonly variable additions.
Jeff Fink, 1992
Added complete-word-fwd, and complete-word-back editor functions
Harry C. Pulley, 1992
Coherent port
Andy Phillips, Mullard Space Science Lab U.K., 1992
VMS-POSIX port.
Beto Appleton, IBM Corp., 1992
Walking process group fixes, lots of misc csh bug fixes, POSIX file
tests, POSIX SIGHUP.
Scott Bolte, Cray Computer Corp., 1992
CSOS port.
Kaveh R. Ghazi, Rutgers University, 1992
Fixes and Ports for Tek, m88k, Titan, Masscomp.
Mark Linderman, Cornell University, 1992
OS/2 Port, (he does not run OS/2 anymore so he cannot help you porting
tcsh on it)
Mika Liljeberg, liljeber@kruuna.Helsinki.FI, 1992
Linux port.
Scott Krotz, Motorola, 1991
Minix port.
David Dawes, Sydney U. Australia, Physics dept., 1991
SVR4 job control fixes. (reverse pipeline startup code, and signal
fixes).
Jose Sousa, Interactive Systems Corp., 1991
Extended vi fixes. Added delete command in vi.
Marc Horowitz, MIT, 1991
Ansification fixes, new exec hashing code, imake fixes, where builtin.
Eric Schnoebelen, Convex, 1990
Convex support, lots of csh bug fixes, save and restore of directory
stack.
Jaap Vermeulen, Sequent, 1990-91
Vi mode fixes, expand-line, window change fixes, ported to symmetry
machines.
Ron Flax, Apple, 1990
Ported again to A/UX 2.0
Dan Oscarsson, LTH Sweden, 1990
NLS support and simulated for non NLS sites. Correction of file names
also handles the case when the / is replaced by another character. The
editor does not switch into cbreak mode unless needed. The shell will
not use character attributes when output is not to a tty.
Johan Widen, SICS Sweden, 1990
Shell level variable, mach support, correct-line, 8-bit printing.
Matt Day, Sanyo Icon, 1990
Added POSIX termio support; Fixed limit stuff for SysV.
Hans J. Albertsson (Sun Sweden)
Added the ampm variable handling, DING!, and the settc and telltc
builtins.
Michael Bloom
Fixed some of the interrupt handling.
Michael Fine, Digital Equipment Corp
added the extended key support.
Daniel Long, NNSC, 1988
Added the wordchars variable.
George Hartzell, MCD Biology, University of Colorado-Boulder, 1988
Fixed the always resetting to DEL bug.
Patrick Wolfe, Kuck and Associates, Inc., 1988
Cleaned up VI mode and wrote the new editor description (in section 1).
Jak Kirman, 1988
Fixed the SunOS 4 giant stack allocation bug.
Bruce Robertson, Tektronix, 1989
Fixed setting erase and kill (again).
David C Lawrence, Rensselaer Polytechnic Institute, 1989
Added "autolist" variable and code to list possibilities on ambiguous
completion.
Martin Boyer, Institut de recherche d'Hydro-Quebec, 1991.
Modified "autolist" variable and code to give options on beeping
behavior. Modified the history search to search for the whole string
from the beginning of the line to the cursor.
Alec Wolman, DEC, 1989
Added code to allow newlines in the prompt.
Matt Landau, BBN, 1989
Fixed YP bugs on Suns, added .tcshrc stuff.
Ray Moody, Purdue Physics, 1989
Added the code to do magic spacebar history expansion.
Mordechai ????, Intel, 1989
Re-arranged the printprompt() routine to use a switch(*cp) (rather than a
bunch of ifs), and added a few things to it.
Josh Siegel, dspo.gov, 1989
Fixed "fg-editor" and added the status line shell variables "sl" and
"el".
Karl Berry, UMB, 1989
Fixed a bug involving environ (in sh.func.c) on NeXT computers.
Michael Greim, Universitaet des Saarlandes, Saarbruecken, W-Germany,
Fixed the nested backquote bug (yes, you can do it; think about aliases)
in 4.2 csh. This fix was posted to comp.bugs.4bsd.
Kazuhiro Honda, Department of Computer Science, Keio University, 1989
Added the code for automatic spelling correction, the prompt3 stuff (the
autocorrect prompt), and HOSTTYPE symbols for the Sony NEWS.
Paul Placeway, BBN, 1990
Fixed character redrawing code insert bugs, and made redrawing code
handle multiple character movement, insert, and delete (if it exists).
Fixed setting of SHELL.
Per Hedeland, Ellemtel, Sweden, 1990
Various bugfixes and improvements, e.g. in history expansion, autolist,
added autoexpand, updated the manual.
THANKS TO
A special thanks to: Bryan Dunlap, Clayton Elwell, Karl Kleinpaste, Bob
Manson, Steve Romig, Diana Smetters, Bob Sutterfield, Mark Verber,
Elizabeth Zwicky, and all the other people at Ohio State for suggestions
and encouragement.
Also, thanks to all the people on the net for putting up with, reporting
bugs in, and suggesting new additions to the old tcsh editor.
