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)