NAME

       erl_prim_loader - Low-level Erlang loader.

DESCRIPTION

       This  module  is used to load all Erlang modules into the system. The start script is also
       fetched with this low-level loader.

       erl_prim_loader knows about the environment and how to fetch modules.

       Command-line flag -loader Loader can be used to choose the method used by erl_prim_loader.
       Two Loader methods are supported by the Erlang runtime system: efile and inet.

EXPORTS

       get_file(Filename) -> {ok, Bin, FullName} | error

              Types:

                 Filename = atom() | string()
                 Bin = binary()
                 FullName = string()

              Fetches  a file using the low-level loader. Filename is either an absolute filename
              or only the name of the file, for example, "lists.beam". If an internal path is set
              to the loader, this path is used to find the file. FullName is the complete name of
              the fetched file. Bin is the contents of the file as a binary.

              Filename   can   also    be    a    file    in    an    archive,    for    example,
              $OTPROOT/lib/mnesia-4.4.7.ez/mnesia-4.4.7/ebin/mnesia.beam.  For  information about
              archive files, see code(3erl).

       get_path() -> {ok, Path}

              Types:

                 Path = [Dir :: string()]

              Gets the path set in the  loader.  The  path  is  set  by  the  init(3erl)  process
              according to information found in the start script.

       list_dir(Dir) -> {ok, Filenames} | error

              Types:

                 Dir = string()
                 Filenames = [Filename :: string()]

              Lists  all  the  files  in  a  directory.  Returns  {ok,  Filenames} if successful,
              otherwise error. Filenames is a  list  of  the  names  of  all  the  files  in  the
              directory. The names are not sorted.

              Dir    can    also    be    a    directory    in    an    archive,   for   example,
              $OTPROOT/lib/mnesia-4.4.7.ez/mnesia-4.4.7/ebin.  For  information   about   archive
              files, see code(3erl).

       read_file_info(Filename) -> {ok, FileInfo} | error

              Types:

                 Filename = string()
                 FileInfo = file:file_info()

              Retrieves information about a file. Returns {ok, FileInfo} if successful, otherwise
              error. FileInfo is a record file_info, defined in the Kernel include file file.hrl.
              Include the following directive in the module from which the function is called:

              -include_lib("kernel/include/file.hrl").

              For more information about the record file_info, see file(3erl).

              Filename    can    also    be    a    file    in    an    archive,   for   example,
              $OTPROOT/lib/mnesia-4.4.7.ez/mnesia-4.4.7/ebin/mnesia.   For   information    about
              archive files, see code(3erl).

       read_link_info(Filename) -> {ok, FileInfo} | error

              Types:

                 Filename = string()
                 FileInfo = file:file_info()

              Works like read_file_info/1 except that if Filename is a symbolic link, information
              about the link is returned in the file_info record and the type field of the record
              is set to symlink.

              If  Filename  is not a symbolic link, this function returns exactly the same result
              as read_file_info/1. On platforms that do not support symbolic links, this function
              is always equivalent to read_file_info/1.

       set_path(Path) -> ok

              Types:

                 Path = [Dir :: string()]

              Sets  the  path  of the loader if init(3erl) interprets a path command in the start
              script.

COMMAND-LINE FLAGS

       The erl_prim_loader module interprets the following command-line flags:

         -loader Loader:
           Specifies the name of the loader used by erl_prim_loader. Loader can be efile (use the
           local file system) or inet (load using the boot_server on another Erlang node).

           If flag -loader is omitted, it defaults to efile.

         -loader_debug:
           Makes  the efile loader write some debug information, such as the reason for failures,
           while it handles files.

         -hosts Hosts:
           Specifies which other Erlang nodes the inet loader can use. This flag is mandatory  if
           flag  -loader  inet  is  present.  On each host, there must be on Erlang node with the
           erl_boot_server(3erl), which handles  the  load  requests.  Hosts  is  a  list  of  IP
           addresses (hostnames are not acceptable).

         -setcookie Cookie:
           Specifies  the  cookie  of  the  Erlang runtime system. This flag is mandatory if flag
           -loader inet is present.

SEE ALSO

       init(3erl), erl_boot_server(3erl)