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* Copyright (c) 2001, 2006 Michael J. Roberts
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* This file is part of TADS 3.
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* This module defines classes and constants related to the File
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* intrinsic class. In particular, this module defines the Exception
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* subclasses thrown by File methods.
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/* ------------------------------------------------------------------------ */
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* File Exception classes. All File exceptions derive from FileException,
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* to allow for generic 'catch' clauses which catch any file-related
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class FileException: Exception
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displayException() { "file error"; }
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* File not found - this is thrown when attempting to open a file for
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* reading and the file doesn't exist or can't be opened (because the user
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* doesn't have privileges to read the file, or the file is already being
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* used by another user, for example).
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class FileNotFoundException: FileException
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displayException() { "file not found"; }
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* File creation error - this is thrown when attempting to open a file for
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* writing and the file can't be created; this can happen because the disk
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* or the directory is full, due to privilege failures, or due to sharing
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* violations, among other reasons.
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class FileCreationException: FileException
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displayException() { "cannot create file"; }
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* File cannot be opened - this is thrown when attempting to open a file
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* for reading and writing but the file can't be opened. This can happen
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* for numerous reasons: sharing violations, privilege failures, lack of
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* space on the disk or in the directory.
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class FileOpenException: FileException
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displayException() { "cannot open file"; }
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* File synchronization exception. This is thrown when an operation
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* (such as a read or write) is attempted during normal execution on a
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* file object that was originally opened during pre-initialization. A
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* file object created during pre-initialization can't be used to access
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* the file during ordinary execution, since the state of the external
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* file might have changed since the pre-init session ended. In such
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* cases, a new file object must be created instead.
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class FileSyncException: FileException
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displayException() { "file synchronization error"; }
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* File closed - this is thrown when an operation is attempted on a file
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* that has already been explicitly closed.
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class FileClosedException: FileException
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displayException() { "operation attempted on closed file"; }
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* File I/O exception - this is thrown when a read or write operation on a
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* file fails. This can indicate, for example, that the device containing
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* the file is full, or that a physical media error occurred.
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class FileIOException: FileException
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displayException() { "file I/O error"; }
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* File mode error - this is thrown when an attempted operation is
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* incompatible with the file's mode. This is thrown under these
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* - writing to a file opened for read-only access
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*. - reading from a file opened for write-only access
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*. - calling readFile or writeFile on a raw-mode file
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*. - calling readBytes or writeBytes on a non-raw-mode file
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class FileModeException: FileException
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displayException() { "invalid file mode"; }
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* File safety error - this is thrown when an attempted "open" operation
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* is prohibited by the current file safety level set by the user.
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class FileSafetyException: FileException
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"file operation prohibited by user-specified file safety level";
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/* export the file exceptions for use by the intrinsic class */
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export FileNotFoundException 'File.FileNotFoundException';
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export FileCreationException 'File.FileCreationException';
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export FileOpenException 'File.FileOpenException';
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export FileIOException 'File.FileIOException';
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export FileSyncException 'File.FileSyncException';
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export FileClosedException 'File.FileClosedException';
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export FileModeException 'File.FileModeException';
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export FileSafetyException 'File.FileSafetyException';
added
removed
tads/tads3/lib/file.t
