environment

早期freebsd实现

Environment variables

	CALCPATH

	    A :-separated list of directories used to search for
	    scripts filenames that do not begin with /, ./ or ~.

	    If this variable does not exist, a compiled value
	    is used.  Typically compiled in value is:

			.:./lib:~/lib:${LIBDIR}/calc
	
	    where ${LIBDIR} is usually:

			/usr/local/lib/calc

	    This value is used by the READ command.  It is an error
	    if no such readable file is found.
	
	
	CALCRC

	    On startup (unless -h or -q was given on the command
	    line), calc searches for files along the :-separated
	    $CALCRC environment variable.

	    If this variable does not exist, a compiled value
	    is used.  Typically compiled in value is:

			${LIBDIR}/startup:~/.calcrc
	
	    where ${LIBDIR} is usually:

			/usr/local/lib/calc

	    Missing files along the $CALCRC path are silently ignored.
	
	CALCBINDINGS

	    On startup (unless -h or -q was given on the command
	    line), calc reads key bindings from the filename specified
	    in the $CALCRC environment variable.  These key bindings
	    are used for command line editing and the command history.

	    If this variable does not exist, a compiled value is used.
	    Typically compiled in value is:

			${LIBDIR}/bindings
	
	    where ${LIBDIR} is usually:

			/usr/local/lib/calc

	    If the file could not be opened, or if standard input is not
	    a terminal, then calc will still run, but fancy command line
	    editing is disabled.

	HOME

	    This value is taken to be the home directory of the
	    current user.  It is used when files begin with '~/'.

	    If this variable does not exist, the home directory password 
	    entry of the current user is used.  If that information
	    is not available, '.' is used.
	
	PAGER

	    When invoking help, this environment variable is used
	    to display a help file.

	    If this variable does not exist, a compiled value
	    is used.  Typically compiled in value is something
	    such as 'more', 'less', 'pg' or 'cat'.
	
	SHELL

	    When a !-command is used, the program indicated by
	    this environment variable is used.

	    If this variable does not exist, a compiled value
	    is used.  Typically compiled in value is something
	    such as 'sh' is used.