An input stream that allows you to read from a file.
| file | file to read from |
| ioFlags | file open flags listed in prio.h (see PR_Open documentation) or -1 to open the file in default mode (PR_RDONLY). |
| perm | file mode bits listed in prio.h or -1 to use the default value (0) |
| behaviorFlags | flags specifying various behaviors of the class (see enumerations in the class) |
If this is set, the file will be deleted by the time the stream is
closed. It may be removed before the stream is closed if it is possible
to delete it and still read from it.
If OPEN_ON_READ is defined, and the file was recreated after the first
delete, the file will be deleted again when it is closed again.
If this is set, the file will close automatically when the end of the
file is reached.
If this is set, the file will be reopened whenever we reach the start of
the file, either by doing a Seek(0, NS_SEEK_CUR), or by doing a relative
seek that happen to reach the beginning of the file. If the file is
already open and the seek occurs, it will happen naturally. (The file
will only be reopened if it is closed for some reason.)
If this is set, the file will be opened (i.e., a call to
PR_Open done) only when we do an actual operation on the stream,
or more specifically, when one of the following is called:
- Seek
- Tell
- SetEOF
- Available
- Read
- ReadLine
DEFER_OPEN is useful if we use the stream on a background
thread, so that the opening and possible |stat|ing of the file
happens there as well.
@note Using this flag results in the file not being opened
during the call to Init. This means that any errors that might
happen when this flag is not set would happen during the
first read. Also, the file is not locked when Init is called,
so it might be deleted before we try to read from it.
This flag has no effect and is totally ignored on any platform except
Windows since this is the default behavior on POSIX systems. On Windows
if this flag is set then the stream is opened in a special mode that
allows the OS to delete the file from disk just like POSIX.