erl_prim_loader(3erl)

1erl_prim_loader(3)         Erlang Module Definition         erl_prim_loader(3)
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NAME

6       erl_prim_loader - Low-level Erlang loader.
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DESCRIPTION

9       This  module  is  used  to load all Erlang modules into the system. The
10       start script is also fetched with this low-level loader.
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12       erl_prim_loader knows about the environment and how to fetch modules.
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14       Command-line flag -loader Loader can be used to choose the method  used
15       by erl_prim_loader. Two Loader methods are supported by the Erlang run‐
16       time system: efile and inet.
17

EXPORTS

19       get_file(Filename) -> {ok, Bin, FullName} | error
20
21              Types:
22
23                 Filename = atom() | string()
24                 Bin = binary()
25                 FullName = string()
26
27              Fetches a file using the low-level loader. Filename is either an
28              absolute  filename  or  only  the name of the file, for example,
29              "lists.beam". If an internal path is set  to  the  loader,  this
30              path  is used to find the file. FullName is the complete name of
31              the fetched file. Bin is the contents of the file as a binary.
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33              Filename can also be a file in an archive,  for  example,  $OTP‐
34              ROOT/lib/mnesia-4.4.7.ez/mnesia-4.4.7/ebin/mnesia.beam.  For in‐
35              formation about archive files, see code(3).
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37       get_path() -> {ok, Path}
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39              Types:
40
41                 Path = [Dir :: string()]
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43              Gets the path set in the loader. The path is set by the  init(3)
44              process according to information found in the start script.
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46       list_dir(Dir) -> {ok, Filenames} | error
47
48              Types:
49
50                 Dir = string()
51                 Filenames = [Filename :: string()]
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53              Lists  all  the files in a directory. Returns {ok, Filenames} if
54              successful, otherwise error. Filenames is a list of the names of
55              all the files in the directory. The names are not sorted.
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57              Dir  can  also  be a directory in an archive, for example, $OTP‐
58              ROOT/lib/mnesia-4.4.7.ez/mnesia-4.4.7/ebin.   For    information
59              about archive files, see code(3).
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61       read_file_info(Filename) -> {ok, FileInfo} | error
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63              Types:
64
65                 Filename = string()
66                 FileInfo = file:file_info()
67
68              Retrieves  information  about  a file. Returns {ok, FileInfo} if
69              successful, otherwise error. FileInfo is a record file_info, de‐
70              fined in the Kernel include file file.hrl. Include the following
71              directive in the module from which the function is called:
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73              -include_lib("kernel/include/file.hrl").
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75              For more information about the record file_info, see file(3).
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77              Filename can also be a file in an archive,  for  example,  $OTP‐
78              ROOT/lib/mnesia-4.4.7.ez/mnesia-4.4.7/ebin/mnesia.  For informa‐
79              tion about archive files, see code(3).
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81       read_link_info(Filename) -> {ok, FileInfo} | error
82
83              Types:
84
85                 Filename = string()
86                 FileInfo = file:file_info()
87
88              Works like read_file_info/1 except that if Filename  is  a  sym‐
89              bolic  link,  information  about  the  link  is  returned in the
90              file_info record and the type field of the record is set to sym‐
91              link.
92
93              If  Filename  is  not a symbolic link, this function returns ex‐
94              actly the same result as read_file_info/1. On platforms that  do
95              not  support  symbolic links, this function is always equivalent
96              to read_file_info/1.
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98       set_path(Path) -> ok
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100              Types:
101
102                 Path = [Dir :: string()]
103
104              Sets the path of the loader if init(3) interprets a path command
105              in the start script.
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COMMAND-LINE FLAGS

108       The erl_prim_loader module interprets the following command-line flags:
109
110         -loader Loader:
111           Specifies  the  name  of the loader used by erl_prim_loader. Loader
112           can be efile (use the local file system) or inet  (load  using  the
113           boot_server on another Erlang node).
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115           If flag -loader is omitted, it defaults to efile.
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117         -loader_debug:
118           Makes  the  efile  loader write some debug information, such as the
119           reason for failures, while it handles files.
120
121         -hosts Hosts:
122           Specifies which other Erlang nodes the inet loader  can  use.  This
123           flag  is  mandatory  if flag -loader inet is present. On each host,
124           there must be on Erlang node  with  the  erl_boot_server(3),  which
125           handles  the  load requests. Hosts is a list of IP addresses (host‐
126           names are not acceptable).
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128         -setcookie Cookie:
129           Specifies the cookie of the Erlang runtime  system.  This  flag  is
130           mandatory if flag -loader inet is present.
131

NAME

DESCRIPTION

EXPORTS

COMMAND-LINE FLAGS

SEE ALSO