`load'
------

load("FILENAME")
     :: Reads a program file FILENAME.

RETURN
     (1|0)

FILENAME
     file (path) name

   * See *Note User language Asir:: for practical programming.  Since
     text files are read through `cpp', the user can use, as in C
     programs, `#include' and `#define' in Asir program source codes.

   * It returns 1 if the designated file exists, 0 otherwise.

   * If the FILENAME begins with `/', it is understood as an absolute
     path name; with  `.', relative path name from current directory;
     otherwise, the file is searched first from directories assigned to
     an environmental variable `ASIRLOADPATH', then if the search ends
     up in failure, the standard library directory (or directories
     assigned to `ASIR_LIBDIR') shall be searched.  On Windows,
     `get_rootdir()/lib' is searched if `ASIR_LIBDIR' is not set.

   * We recommend to write an `end' command at the last line of your
     program.  If not, Asir will not give you a prompt after it will
     have executed `load' command.  (Escape with an interrupt character
     (*Note Interruption::), if you have lost yourself.)  Even in such
     a situation, Asir itself is still ready to read keyboard inputs as
     usual.  It is, however, embarrassing and may cause other errors.
     Therefore, to put an `end$' at the last line is desirable.
     (Command `end;' will work as well, but it also returns and
     displays verbose.)

   * On Windows one has to use `/' as the separator of directory names.

References
     *Note `end quit': end quit, *Note `which': which, *Note
     `get_rootdir': get_rootdir.

