IoLib (luna-all-shaded 0.3 API)

java.lang.Object
- org.classdump.luna.lib.IoLib

```
public final class IoLib
extends Object
```
The I/O library provides two different styles for file manipulation. The first one uses implicit file handles; that is, there are operations to set a default input file and a default output file, and all input/output operations are over these default files. The second style uses explicit file handles.

When using implicit file handles, all operations are supplied by table io. When using explicit file handles, the operation io.open returns a file handle and then all operations are supplied as methods of the file handle.

The table io also provides three predefined file handles with their usual meanings from C: io.stdin, io.stdout, and io.stderr. The I/O library never closes these files.
Unless otherwise stated, all I/O functions return nil on failure (plus an error message as a second result and a system-dependent error code as a third result) and some value different from nil on success. On non-POSIX systems, the computation of the error message and error code in case of errors may be not thread safe, because they rely on the global C variable errno.

Method Summary

All Methods Static Methods Concrete Methods
Modifier and Type	Method and Description
`static org.classdump.luna.runtime.LuaFunction`	`file_close()` Returns the file method (a function) `close`.
`static org.classdump.luna.runtime.LuaFunction`	`file_flush()` Returns the file method (a function) `flush`.
`static org.classdump.luna.runtime.LuaFunction`	`file_lines()` Returns the file method (a function) `lines`.
`static org.classdump.luna.runtime.LuaFunction`	`file_read()` Returns the file method (a function) `read`.
`static org.classdump.luna.runtime.LuaFunction`	`file_seek()` Returns the file method (a function) `seek`.
`static org.classdump.luna.runtime.LuaFunction`	`file_setvbuf()` Returns the file method (a function) `setvbuf`.
`static org.classdump.luna.runtime.LuaFunction`	`file_tostring()` Returns the file method (a function) `tostring`.
`static org.classdump.luna.runtime.LuaFunction`	`file_write()` Returns the file method (a function) `write`.
`static void`	`installInto(org.classdump.luna.StateContext context, org.classdump.luna.Table env, RuntimeEnvironment runtimeEnvironment)` Installs the I/O library to the global environment `env` in the state context `context`.
`static org.classdump.luna.runtime.LuaFunction`	`type()` Returns the function `io.type`.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Method Detail
  - type
```
public static org.classdump.luna.runtime.LuaFunction type()
```
    Returns the function io.type.
    The following is the corresponding entry from the Lua Reference Manual:
    
    io.type (obj)
    Checks whether obj is a valid file handle. Returns the string "file" if obj is an open file handle, "closed file" if obj is a closed file handle, or nil if obj is not a file handle.
    
    Returns:
    
    the io.type function
    
    See Also:
    
    the Lua 5.3 Reference Manual entry for io.type
  - file_close
```
public static org.classdump.luna.runtime.LuaFunction file_close()
```
    Returns the file method (a function) close.
    The following is the corresponding entry from the Lua Reference Manual:
    
    file:close ()
    Closes file. Note that files are automatically closed when their handles are garbage collected, but that takes an unpredictable amount of time to happen.
    
    When closing a file handle created with io.popen, file:close returns the same values returned by os.execute.
    
    Returns:
    
    the file:close method
    
    See Also:
    
    the Lua 5.3 Reference Manual entry for file:close
  - file_flush
```
public static org.classdump.luna.runtime.LuaFunction file_flush()
```
    Returns the file method (a function) flush.
    The following is the corresponding entry from the Lua Reference Manual:
    
    file:flush ()
    Saves any written data to file.
    
    Returns:
    
    the file:flush method
    
    See Also:
    
    the Lua 5.3 Reference Manual entry for file:flush
  - file_lines
```
public static org.classdump.luna.runtime.LuaFunction file_lines()
```
    Returns the file method (a function) lines.
    The following is the corresponding entry from the Lua Reference Manual:
    file:lines (···)
    Returns an iterator function that, each time it is called, reads the file according to the given formats. When no format is given, uses "l" as a default. As an example, the construction
    
    for c in file:lines(1) do body end
    
    will iterate over all characters of the file, starting at the current position. Unlike io.lines, this function does not close the file when the loop ends.
    
    In case of errors this function raises the error, instead of returning an error code.
    Returns:
    
    the file:lines method
    
    See Also:
    
    the Lua 5.3 Reference Manual entry for file:lines
  - file_read
```
public static org.classdump.luna.runtime.LuaFunction file_read()
```
    Returns the file method (a function) read.
    The following is the corresponding entry from the Lua Reference Manual:
    file:read (···)
    Reads the file file, according to the given formats, which specify what to read. For each format, the function returns a string or a number with the characters read, or nil if it cannot read data with the specified format. (In this latter case, the function does not read subsequent formats.) When called without formats, it uses a default format that reads the next line (see below).
    
    The available formats are
    
    "n": reads a numeral and returns it as a float or an integer, following the lexical conventions of Lua. (The numeral may have leading spaces and a sign.) This format always reads the longest input sequence that is a valid prefix for a numeral; if that prefix does not form a valid numeral (e.g., an empty string, "0x", or "3.4e-"), it is discarded and the function returns nil.
    
    "a": reads the whole file, starting at the current position. On end of file, it returns the empty string.
    
    "l": reads the next line skipping the end of line, returning nil on end of file. This is the default format.
    
    "L": reads the next line keeping the end-of-line character (if present), returning nil on end of file.
    
    number: reads a string with up to this number of bytes, returning nil on end of file. If number is zero, it reads nothing and returns an empty string, or nil on end of file.
    
    The formats "l" and "L" should be used only for text files.
    Returns:
    
    the file:read method
    
    See Also:
    
    the Lua 5.3 Reference Manual entry for file:read
  - file_seek
```
public static org.classdump.luna.runtime.LuaFunction file_seek()
```
    Returns the file method (a function) seek.
    The following is the corresponding entry from the Lua Reference Manual:
    file:seek ([whence [, offset]])
    Sets and gets the file position, measured from the beginning of the file, to the position given by offset plus a base specified by the string whence, as follows:
    
    "set": base is position 0 (beginning of the file);
    
    "cur": base is current position;
    
    "end": base is end of file;
    
    In case of success, seek returns the final file position, measured in bytes from the beginning of the file. If seek fails, it returns nil, plus a string describing the error.
    
    The default value for whence is "cur", and for offset is 0. Therefore, the call file:seek() returns the current file position, without changing it; the call file:seek("set") sets the position to the beginning of the file (and returns 0); and the call file:seek("end") sets the position to the end of the file, and returns its size.
    Returns:
    
    the file:seek method
    
    See Also:
    
    the Lua 5.3 Reference Manual entry for file:seek
  - file_setvbuf
```
public static org.classdump.luna.runtime.LuaFunction file_setvbuf()
```
    Returns the file method (a function) setvbuf.
    The following is the corresponding entry from the Lua Reference Manual:
    file:setvbuf (mode [, size])
    Sets the buffering mode for an output file. There are three available modes:
    
    "no": no buffering; the result of any output operation appears immediately.
    
    "full": full buffering; output operation is performed only when the buffer is full or when you explicitly flush the file (see io.flush).
    
    "line": line buffering; output is buffered until a newline is output or there is any input from some special files (such as a terminal device).
    
    For the last two cases, size specifies the size of the buffer, in bytes. The default is an appropriate size.
    Returns:
    
    the file:setvbuf method
    
    See Also:
    
    the Lua 5.3 Reference Manual entry for file:setvbuf
  - file_tostring
```
public static org.classdump.luna.runtime.LuaFunction file_tostring()
```
    Returns the file method (a function) tostring.
    
    Returns:
    
    the file:tostring method
  - file_write
```
public static org.classdump.luna.runtime.LuaFunction file_write()
```
    Returns the file method (a function) write.
    The following is the corresponding entry from the Lua Reference Manual:
    
    file:write (···)
    Writes the value of each of its arguments to file. The arguments must be strings or numbers.
    
    In case of success, this function returns file. Otherwise it returns nil plus a string describing the error.
    
    Returns:
    
    the file:write method
    
    See Also:
    
    the Lua 5.3 Reference Manual entry for file:write
  - installInto
```
public static void installInto(org.classdump.luna.StateContext context,
                               org.classdump.luna.Table env,
                               RuntimeEnvironment runtimeEnvironment)
```
    Installs the I/O library to the global environment env in the state context context. The I/O functions will use the runtime environment runtimeEnvironment.
    If env.package.loaded is a table, adds the library table to it with the key "io", using raw access.
    
    Parameters:
    
    context - the state context, must not be null
    
    env - the global environment, must not be null
    
    runtimeEnvironment - the runtime environment, may be null
    
    Throws:
    
    NullPointerException - if context or env is null

Class IoLib

Method Summary

Methods inherited from class java.lang.Object

Method Detail

type

file_close

file_flush

file_lines

file_read

file_seek

file_setvbuf

file_tostring

file_write

installInto