File objects, Roappendfile – BrightSign Object Reference Manual (FW 5.1) User Manual
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FILE OBJECTS
roAppendFile
This object can be used to create a new file or append information to the end of an existing file.
CreateObject("roAppendFile", filename As String): Creating an roAppendFile object opens an existing
file or creates a new file. The current position is set to the end of the file, and all writes are made to the end of the file.
The ifStreamRead interface provides the following:
•
SetReceiveEol(eol_sequence As String) As Void: Sets the EOL sequence when reading from the
stream.
•
ReadByte() As Integer: Reads a single byte from the stream, blocking if necessary. If the EOF is reached or
there is an error condition, then a value less than 0 is returned.
•
ReadByteIfAvailable() As Integer: Reads a single byte from the stream if one is available. If no bytes are
available, it returns immediately. A return value less than 0 indicates either that the EOF has been reached or no
byte is available.
•
ReadLine() As String: Reads until it finds a complete end of the line sequence. If it fails to find the sequence
within 4096 bytes, then it returns the 4096 bytes that are found. No data is discarded in this case.
•
ReadBlock(size As Integer) As String: Reads the specified number of bytes. The number is limited to
65536 bytes. In the event of an EOF or an error, fewer bytes than requested will be returned. Any null bytes in the
file will mask any further bytes.