Startup and shutdown
A login shell begins by executing commands from the system files /etc/csh.cshrc and /etc/csh.login.
It then executes commands from files in the user's home directory: first ~/.tcshrc (+) or, if
~/.tcshrc is not found, ~/.cshrc, then ~/.history (or the value of the histfile shell variable), then
~/.login, and finally ~/.cshdirs (or the value of the dirsfile shell variable) (+). The shell may
read /etc/csh.login before instead of after /etc/csh.cshrc, and ~/.login before instead of after
~/.tcshrc or ~/.cshrc and ~/.history, if so compiled; see the version shell variable. (+)
Non-login shells read only /etc/csh.cshrc and ~/.tcshrc or ~/.cshrc on startup.
Builtin and non-builtin command execution
Builtin commands are executed within the shell. If any component of a pipeline except the last is a
builtin command, the pipeline is executed in a subshell.
Parenthesized commands are always executed in a subshell.
(cd; pwd); pwd
thus prints the home directory, leaving you where you were (printing this after the home directory),
while
cd; pwd
leaves you in the home directory. Parenthesized commands are most often used to prevent cd from
affecting the current shell.
When a command to be executed is found not to be a builtin command the shell attempts to execute the
command via execve(2).
[...]
builtins (+)
Prints the names of all builtin commands.
setenv [name [value]]
Without arguments, prints the names and values of all environment variables. Given name,
sets the environment variable name to value or, without value, to the null string.
tcsh (+)
The version number of the shell in the format `R.VV.PP', where `R' is the major release num-ber, number,
ber, `VV' the current version and `PP' the patchlevel.
version (+)
The version ID stamp. It contains the shell's version number (see tcsh), origin, release
date, vendor, operating system and machine (see VENDOR, OSTYPE and MACHTYPE) and a comma-sep-arated comma-separated
arated list of options which were set at compile time. Options which are set by default in
the distribution are noted.
VERSION
This manual documents tcsh 6.17.00 (Astron) 2009-07-10.
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