Tcshrc example file

With -L , the shell appends filename , which is presumably a history list saved by the -S option or the savehist mechanism, to the history list. If histlit is set, the first and second forms print and save the literal unexpanded form of the history list.

The last form clears the history list. Note that commands may set their own response to hangups, overriding hup. Without an argument allowed in only a shell script , causes the shell to exit on a hangup for the remainder of the script. See also Signal handling and the nohup builtin command. Variable substitution on command happens early, at the same time it does for the rest of the if command.

Any number of else-if pairs are possible; only one endif is needed. The else part is likewise optional. The words else and endif must appear at the beginning of input lines; the if must appear alone on its input line or after an else.

There is no way to remove a shared library. With -l , lists process IDs in addition to the normal information. On TCF systems, prints the site on which each job is executing.

The third form lists the signal names. If no maximum-use is given, then the current limit is printed; if no resource is given, then all limitations are given. If the -h flag is given, the hard limits are used instead of the current limits. The hard limits impose a ceiling on the values of the current limits.

Only the super-user may raise the hard limits, but a user may lower or raise the current limits within the legal range. The value is meaningless and changing this value will have no effect heapsize the maximum amount of memory a process may allocate per brk system call descriptors or openfiles the maximum number of open files for this process concurrency the maximum number of threads for this process memorylocked the maximum size which a process may lock into memory using mlock 2 maxproc the maximum number of simultaneous processes for this user id sbsize the maximum size of socket buffer usage for this user maximum-use may be given as a floating point or integer number followed by a scale factor.

For both resource names and scale factors, unambiguous prefixes of the names suffice. See also watchlog. This is one way to log off, included for compatibility with sh 1.

Especially useful if ignoreeof is set. The ls-F builtin can list files using different colors depending on the filetype or extension. Migrating the shell itself can cause unexpected behavior, because the shell does not like to lose its tty. With command , runs command at the appropriate priority. The greater the number , the less cpu the process gets. Command is always executed in a sub-shell, and the restrictions placed on commands in simple if statements apply. Note that commands may set their own response to hangups, overriding nohup.

Without an argument allowed in only a shell script , causes the shell to ignore hangups for the remainder of the script. See also Signal handling and the hup builtin command. See also the notify shell variable. Without arguments, restores the default action of the shell on interrupts, which is to terminate shell scripts or to return to the terminal command input level.

Finally, all forms of popd print the final directory stack, just like dirs. The pushdsilent shell variable can be set to prevent this and the -p flag can be given to override pushdsilent. The -l , -n and -v flags have the same effect on popd as on dirs. The -l , -n and -v flags have the same effect on pushd as on dirs. This is needed if new commands are added to directories in path while you are logged in.

This should be necessary only if you add commands to one of your own directories, or if a systems programmer changes the contents of one of the system directories. Also flushes the cache of home directories built by tilde expansion. The sched shell variable may be set to define the format in which the scheduled-event list is printed.

The second form adds command to the scheduled-event list. It is possible to miss the exact time when the command is to be run, but an overdue command will execute at the next prompt. A command which comes due while the shell is waiting for user input is executed immediately.

However, normal operation of an already-running command will not 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 may not run a command at exactly the specified time.

Its major advantage is that because sched runs directly from the shell, it has access to shell variables and other structures. Variables which contain more than a single word print as a parenthesized word list.

The second form sets name to the null string. The third form sets name to the single word. The fourth form sets name to the list of words in wordlist. In all cases the value is command and filename expanded.

If -r is specified, the value is set read-only. If -f or -l are specified, set only unique words keeping their order. The sixth form lists only the names of all shell variables that are read-only. The seventh form makes name read-only, whether or not it has a value.

The eighth form is the same as the third form, but make name read-only at the same time. Note, however, that variable expansion happens for all arguments before any setting occurs. See also the unset builtin command. Given name , sets the environment variable name to value or, without value , to the null string. No sanity checking is done. The available modes, and thus the display, vary from system to system. With -a , lists all tty modes in the chosen set whether or not they are fixed.

TCF only shift [ variable ] Without arguments, discards argv [1] and shifts the members of argv to the left. It is an error for argv not to be set or to have less than one word as value.

With variable , performs the same function on variable. The commands are not placed on the history list. If any args are given, they are placed in argv. An error in a source at any level terminates all nested source commands. Stops the specified jobs or processes which are executing in the background.

This is most often used to stop shells started by su 1. Each case label and the default label must appear at the beginning of a line. The command breaksw causes execution to continue after the endsw. Otherwise control may fall through case labels and default labels as in C.

If no label matches and there is no default, execution continues after the endsw. Prints the terminal type to stdout and returns 0 if an entry is present otherwise returns 1. If necessary, an extra shell is created to print the time statistic when the command completes. Without command , prints a time summary for the current shell and its children.

Common values for the mask are , giving all access to the group and read and execute access to others, and , giving read and execute access to the group and others.

Without value , prints the current file creation mask. It is not an error for nothing to be unalias ed. It is not an error for nothing to be uncomplete d. With -h , the corresponding hard limits are removed. Only the super-user may do this. Note that unlimit may not exit successful, since most systems do not allow descriptors to be unlimited. It is not an error for nothing to be unset.

It is not an error for nothing to be unsetenv ed. With systype and command , executes command under systype. If the shell is interactive, an interrupt will disrupt the wait and cause the shell to print the names and job numbers of all outstanding jobs. The builtin command is just like which 1 , but it correctly reports tcsh aliases and builtins and is 10 to times faster. See also the which-command editor command.

If the input is a terminal, the user is prompted the first time through the loop as with foreach. They are all initially undefined. Tag Description beepcmd Runs when the shell wants to ring the terminal bell. Note that putting a cd , pushd or popd in cwdcmd may cause an infinite loop. This is similar to postcmd , but it does not print builtins. The command name for which help is sought is passed as sole argument.

Currently there is no easy way to account for various calling conventions e. This provides a convenient means for checking on common but infrequent changes such as new mail. If periodic is set but tperiod is unset or set to 0, periodic behaves like precmd.

There are no limits on what precmd can be set to do, but discretion should be used. The first word should be a full path name to the desired interpreter e. Special shell variables The variables described in this section have special meaning to the shell. The shell updates cwd , dirstack , owd and status when necessary, and sets logout on logout. The shell synchronizes afsuser , group , home , path , shlvl , term and user with the environment variables of the same names: whenever the environment variable changes the shell changes the corresponding shell variable to match unless the shell variable is read-only and vice versa.

Note that although cwd and PWD have identical meanings, they are not synchronized in this manner, and that the shell automatically interconverts the different formats of path and PATH.

Set by default. Positional parameters are taken from argv , i. Set by default, but usually empty in interactive shells.

The optional second word is the number of minutes of inactivity before automatic locking. When the shell automatically locks, the user is required to enter his password to continue working.

Five incorrect attempts result in automatic logout. See also the afsuser and logout shell variables. This may make complex quoting tasks easier, but it can cause syntax errors in csh 1 scripts.

Alternatively, it can be set to only ls-F or only ls to enable color to only one command. Setting it to nothing is equivalent to setting it to ls-F ls.

And display colorful NLS messages. See also the dirstack and owd shell variables. One can change the stack arbitrarily by setting dirstack , but the first element the current working directory is always correct.

See also the cwd and owd shell variables. Each character is set to number 0,1,2 and 3. Each number has the following meaning: Then, it is not used for multi-byte characters.

It is used for both the first byte and the second byte of a multi-byte character. The GNU fileutils version of ls cannot display multi-byte filenames without the -N --literal option. If you are using this version, set the second word of dspmbyte to "ls". If not, for example, "ls-F -l" cannot display multi-byte filenames. For non-builtin commands all expansions occur before echoing. Builtin commands are echoed before command and filename substitution, because these substitutions are then done selectively.

Set by the -x command line option. Set by default to the local system default. Set by default in interactive shells. If edit is unset, then the traditional csh completion is used. If set in csh , filename completion is used.

See also the toggle-literal-history editor command. This prevents the shell from accidentally being killed. If set to a number n , the shell ignores n - 1 consecutive end-of-file s and exits on the n th. If set to verbose , the change of directory is echoed to the standard output.

This behavior is inhibited in non-interactive shell scripts, or for command strings with more than one word. Changing directory takes precedence over executing a like-named command, but it is done after alias substitutions. Tilde and variable expansions work as expected. Strings are put in the killring by the editor commands that delete kill strings of text, e. The yank editor command will yank the most recently killed string into the command-line, while yank-pop see Editor commands can be used to yank earlier killed strings.

Setting or unsetting it within a shell has no effect. See also shlvl. See also the autologout shell variable. If you are in a login shell, then no mail file is reported unless it has been modified after the time the shell has started up, to prevent redundant notifications.

Most login programs will tell you whether or not you have mail when you log in. This functionality is provided primarily for those systems which store mail in this manner, such as the Andrew Mail System. If the first word of mail is numeric it is taken as a different mail checking interval, in seconds. See also visiblebell. This is most useful in shell scripts which do not deal with filenames, or after a list of filenames has been obtained and further expansions are not desirable.

It is still an error for the substitution to be malformed, e. The default is to present job completions just before printing a prompt. See also the cwd and dirstack shell variables. A null word specifies the current directory. If there is no path variable then only full path names will execute.

If one adds a new command to a directory in path while the shell is active, one may need to do a rehash for the shell to find it. The current history event number. It should be used only to change terminal attributes and should not move the cursor location. This cannot be the last sequence in prompt.

The return code of the command executed just before the prompt. In prompt3 , the corrected string. In history , the history string. The bold, standout and underline sequences are often used to distinguish a superuser shell. The same format sequences may be used as in prompt q.

It recognizes the same formatting characters as prompt. If the first word is set to a number, at most that many directory stack entries are saved. If the first word is set to a number, at most that many lines are saved. The number must be less than or equal to history.

This is used in forking shells to interpret files which have execute bits set, but which are not executable by the system. See the description of Builtin and non-builtin command execution. Initialized to the system-dependent home of the shell. Reset to 1 in login shells. See also loginsh. If it terminated abnormally, then is added to the status. This affects only builtin commands and filename completion. This affects any command, not just builtins. Unfortunately, this does not work for hard-to-recognize filenames, such as those embedded in command options.

Expansion may be prevented by quoting. While this setting is usually the most convenient, it is sometimes misleading and sometimes confusing when it fails to recognize an argument which should be expanded. Some examples are in order. If there is a second word, it is used as a format string for the output of the time builtin. Only the first four sequences are supported on systems without BSD resource limit functions.

Set by the -v command line option. Options which are set by default in the distribution are noted. An administrator may enter additional strings to indicate differences in the local version. See also nobeep. Logins and logouts are checked every 10 minutes by default, but the first word of watch can be set to a number to check every so many minutes. For the impatient, the log builtin command triggers a watch report at any time. All current logins are reported as with the log builtin when watch is first set.

The who shell variable controls the format of watch reports. See Terminal management. If set, the shell does not set autologout q. HOME Equivalent to the home shell variable. This variable is obsolete and will be removed in a future version. LANG Gives the preferred character environment. See Native Language System support. File names can also be colorized based on filename extension. This would color all files ending in.

This is generally more convenient to use, but less general. If your terminal does use ISO color codes, you can compose the type codes i. The most common commands are: Tag Description Tag Description 0 to restore default color 1 for brighter colors 4 for underlined text 5 for flashing text 30 for black foreground 31 for red foreground 32 for green foreground 33 for yellow or brown foreground 34 for blue foreground 35 for purple foreground 36 for cyan foreground 37 for white or gray foreground 40 for black background 41 for red background 42 for green background 43 for yellow or brown background 44 for blue background 45 for purple background 46 for cyan background 47 for white or gray background Not all commands will work on all systems or display devices.

A few terminal programs do not recognize the default end code properly. If all text gets colorized after you do a directory listing, try changing the no and fi codes from 0 to the numerical codes for your standard fore- and background colors. PATH A colon-separated list of directories in which to look for executables. Equivalent to the path shell variable, but in a different format. Set only if the shell was so compiled; see the version shell variable. USER Equivalent to the user shell variable.

Solaris 2. The order in which startup files are read may differ if the shell was so compiled; see Startup and shutdown and the version shell variable. A command-line editor, which supports GNU Emacs or vi 1 -style key bindings. See The command-line editor and Editor commands. Programmable, interactive word completion and listing. See Completion and listing and the complete and uncomplete builtin commands. Spelling correction q. Editor commands q. An enhanced history mechanism. Events in the history list are time-stamped.

Enhanced directory parsing and directory stack handling. See the cd , pushd , popd and dirs commands and their associated shell variables, the description of Directory stack substitution , the dirstack , owd and symlinks shell variables and the normalize-command and normalize-path editor commands. Negation in glob-patterns. New File inquiry operators q. A variety of Automatic, periodic and timed events q. Extensive terminal-management capabilities. New builtin commands including builtins , hup , ls-F , newgrp , printenv , which and where q.

New variables that make useful information easily available to the shell. A new syntax for including useful information in the prompt string see prompt. Read-only variables. BUGS When a suspended command is restarted, the shell prints the directory it started in if this is different from the current directory. This can be misleading i. This is especially noticeable if this expansion results from an alias. Control over tty output after processes are started is primitive; perhaps this will inspire someone to work on a good virtual terminal interface.

In a virtual terminal interface much more interesting things could be done with output control. Alias substitution is most often used to clumsily simulate shell procedures; shell procedures should be provided rather than aliases. Commands within loops are not placed in the history list.

Control structures should be parsed rather than being recognized as built-in commands. The screen update for lines longer than the screen width is very poor if the terminal cannot move the cursor up i. The single-command form of if does output redirection even if the expression is false and the command is not executed. It cannot be interrupted. Command substitution supports multiple commands and conditions, but not cycles or backward goto s. If you want to help maintain and test tcsh, send mail to tcsh-request mx.

The PDP was a later re-implementation. It was extremely successful in academia. They called their version TOPS their capitalization is trademarked. The system limits argument lists to characters. Command substitutions may substitute no more characters than are allowed in an argument list.

To detect looping, the shell restricts the number of alias substitutions on a single line to SEE ALSO tset 1 , vi 1 , x 1 , access 2 , execve 2 , fork 2 , killpg 2 , pipe 2 , setrlimit 2 , sigvec 2 , stat 2 , umask 2 , vfork 2 , wait 2 , malloc 3 , setlocale 3 , tty 4 , a. Zoulas, Cornell U. EE Dept. Australia, Physics Dept. Added autoconf support. FI , Linux port Tim P. Edward Hutchins, Silicon Graphics Inc. Taga Nayuta, Color ls additions.

Commands are read from the following argument which must be present, and must be a single argument , stored in the command shell variable for reference, and executed. The shell exits if any invoked command terminates abnormally or yields a non-zero exit status. The shell uses fork 2 instead of vfork 2 to spawn processes.

The shell is interactive and prompts for its top-level input, even if it appears to not be a terminal. The shell is a login shell. The shell parses commands but does not execute them. The shell reads and executes a single line of input.

Sets the verbose shell variable, so that command input is echoed after history substitution. Sets the echo shell variable, so that commands are echoed immediately before execution.

Replaces the current word with the first word in the list of possible completions. Copies the previous word in the current line into the input buffer.

Consequently, if a command must be run for each shell that starts up, the command should usually appear in. Commands that need to be run only at login should appear in.

Examples of the latter include:. Commands that affect your terminal settings, like tset, reset , and stty. Commands that set environment variables. Non-login shells inherit environment variables from the login shell, so you need to set those variables only once, using. Commands like biff , which controls the announcement of new mail, or mesg , which determines whether other users can write to your terminal. Commands that produce output. For instance, some people like to execute uptime at login time to find out how busy the system is, msgs —q to see if there are new system messages, who to see who else is logged in, or date to display the current date and time.

A shell can be interactive or non-interactive. An interactive shell interacts with a user, who types commands. A non-interactive shell receives input from another source, such as a script file. Interactive and non-interactive shells have somewhat different capabilities and behaviors. For example, only interactive shells print a prompt or allow you to use job control and command history.

Commands that apply only to interactive shells can be skipped, reducing start up time:. The if -statement tests whether the prompt variable has a value, to distinguish between interactive and non-interactive shells. Commands that are relevant only to interactive shells can be placed between the if and the endif , and non-interactive shells will ignore them.

If you include a set prompt command in your. If you put a lot of stuff in your startup files, they can get pretty long. One way to reduce clutter is to group similar commands into separate files, and then reference them using the source command.

For example, you might put your aliases and command editor key bindings in the files. You could then refer to the files in. Another advantage to this approach is that if you change one of the individual files, you can source it without having to reprocess your entire.

Even if tcsh is your login shell, csh may read your. Some programs are implemented as csh scripts, so. Therefore, you need to be careful about putting tcsh -specific commands in your. An error will occur if csh tries to execute tcsh commands like bindkey or complete.

You can avoid problems by using the following construct to protect tcsh -specific commands from csh. It relies on the fact that tcsh sets the tcsh variable before it reads any startup files and csh does not. The result is that tcsh executes the conditional block and csh ignores it:.

Another approach is to use. A simple way to create. However, later changes may need to be made to both files. As an alternative, you can create a version of. The layout shown below accomplishes this task:. Skip to main content. Start your free trial. Chapter 4. The Shell Startup Files. Terminal settings, such as your backspace and line kill characters Variable values Aliases Key bindings for the command-line editor tcsh only Programmed completions tcsh only. Using Variables. However, when I try:!

How can I get the aliases to work in the new shell? Improve this question. Al Ibrahim Al Ibrahim 1 1 1 bronze badge. I am using Linux Centos 6 — Al Ibrahim.

Add a comment. Active Oldest Votes. Improve this answer. Martin Tournoij Martin Tournoij Thank you for your elegant solution. The problem is that I am unable to edit the. The studio script is used by many users and I will not be able to create a script that modifies their. You can also pass the filename as an environment variable. Thank you very much. It did work using my. Is there is another way to do so without changing.