. filename [arguments]
source filename [arguments]
Read and execute commands from filename in the current
shell environment and return the exit status of the
last command executed from filename. If filename does
not contain a slash, file names in PATH are used to
find the directory containing filename. The file
searched for in PATH need not be executable. When bash
is not in posix mode, the current directory is searched
if no file is found in PATH. If the sourcepath option
to the shopt builtin command is turned off, the PATH is
not searched. If any arguments are supplied, they
become the positional parameters when filename is exe-
cuted. Otherwise the positional parameters are
unchanged. The return status is the status of the last
command exited within the script (0 if no commands are
executed), and false if filename is not found or cannot
be read.