moss.drivers
Class MJavaConsole

java.lang.Object
  moss.drivers.MJavaConsole

All Implemented Interfaces:

MFileOps

public class MJavaConsole
extends java.lang.Object
implements MFileOps

this class provides a MFileOps interface to the Java in/out streams. It is opened once by the init task when the system starts.

Field Summary

Fields inherited from interface moss.fs.MFileOps

F_GETFL, F_OK, F_SETFL, LSEEK_BEG, LSEEK_CUR, LSEEK_END, O_CLOEXEC, O_NONBLOCK, OPEN_CREAT, OPEN_READ, OPEN_TRUNC, OPEN_WRITE, R_OK, W_OK, X_OK

Constructor Summary

MJavaConsole()
constructor; initialises buffer, etc.

Method Summary

int	close(MFile handle) called when closing the console -- should never be called..!
int	fcntl(MFile handle, int op, int arg) file-handle control.
int	lseek(MFile handle, int offset, int whence) not supported by the console
int	open(MFile handle, int flags) called when initialising the console; stores reference to self in the file-handle
int	read(MFile handle, byte[] buffer, int count) called to read data from the keyboard
int	write(MFile handle, byte[] buffer, int count) called to write data to the screen

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

MJavaConsole

public MJavaConsole()

constructor; initialises buffer, etc.

Method Detail

open

public int open(MFile handle,
                int flags)

called when initialising the console; stores reference to self in the file-handle

Specified by:

open in interface MFileOps

Parameters:

handle - file-handle

flags - open flags (ignored)

Returns:

0 on success or < 0 on error

close

public int close(MFile handle)

called when closing the console -- should never be called..!

Specified by:

close in interface MFileOps

Parameters:

handle - file-handle

Returns:

0 on success or < 0 on error

lseek

public int lseek(MFile handle,
                 int offset,
                 int whence)

not supported by the console

Specified by:

lseek in interface MFileOps

Parameters:

handle - file-handle

offset - byte-offset relative to "whence" (block offset for block devices)

whence - constant indicating position seek should occur from

Returns:

new absolute offset or < 0 indicating error

read

public int read(MFile handle,
                byte[] buffer,
                int count)

called to read data from the keyboard

Specified by:

read in interface MFileOps

Parameters:

handle - file-handle

buffer - buffer where data will be stored

count - maximum number of bytes to read

Returns:

number of bytes read, 0 on end-of-file, or < 0 on error

write

public int write(MFile handle,
                 byte[] buffer,
                 int count)

called to write data to the screen

Specified by:

write in interface MFileOps

Parameters:

handle - file handle

buffer - data to write

count - number of bytes to write

Returns:

number of bytes written or < 0 on error

fcntl

public int fcntl(MFile handle,
                 int op,
                 int arg)

file-handle control. The only operation the console supports is to adjust the blocking/non-blocking setting.

Specified by:

fcntl in interface MFileOps

Parameters:

handle - file-handle

op - operation (only F_SETFL supported here)

arg - operation-specific argument (new flags)

Returns:

>= 0 on success, or < 0 indicating failure