Using csh & tcsh

Variables

There are two types of variables: shell variables and environment variables. Shell variables are available only to the shell in which they are defined. Environment variables are available to the current shell and also to other processes (including subshells) that are started from the shell. By convention, shell variables are lowercase and environment variables are uppercase.

Some useful shell variables are listed in the table below.

Variable	Description
autologout	If set, automatic logout occurs after you have been inactive for an hour. If set to a number, logout occurs after that many minutes of inactivity. Some shells set autologout by default at login time. To disable, unset autologout in ˜/.cshrc.
cdpath	A list of directories in which the shell looks for directories specified as arguments to cd or pushd.
correct	If set to cmd, turns on spelling correction for command names. If set to all, turns on spelling correction for the entire command line (tcsh only).
cwd	Set by the shell to your current working directory when your directory changes.
fignore	A list of filename suffixes. Filenames ending with any of the suffixes are ignored for filename completion.
filec	In csh, turns on filename completion. (Unnecessary for tcsh.)
history	If set, specifies the number of commands to save in the history list.
home	The pathname to your home directory.
ignoreeof	If set, CTRL-D does not terminate the shell. You need to explicitly type exit or logout.
mail	Pathname of file to check periodically to see if ...