. file [ arg ... ]
       Read commands from file and execute them in the current shell envi-
       ronment.

       If file does not contain a slash, or if PATH_DIRS is set, the shell
       looks  in  the components of $path to find the directory containing
       file.  Files in the current directory are not read unless  `.'  ap-
       pears  somewhere in $path.  If a file named `file.zwc' is found, is
       newer than file, and is the compiled form (created with  the  zcom-
       pile  builtin)  of  file, then commands are read from that file in-
       stead of file.

       If any arguments arg are given, they become the positional  parame-
       ters;  the  old positional parameters are restored when the file is
       done executing.  However, if no arguments are given, the positional
       parameters remain those of the calling context, and no restoring is
       done.

       If file was not found the return status is 127; if file  was  found
       but contained a syntax error the return status is 126; else the re-
       turn status is the exit status of the last command executed.
