OPEN

OPEN File name FOR [ READ ] [ WRITE ] [ CREATE | APPEND ] [ DIRECT ] [ WATCH ] [ BIG | LITTLE ] AS # Variable

Opens a file for reading, writing, creating or appending data. The file must exist, unless the CREATE keyword is specified.

If the CREATE keyword is specified, then the file is created, or cleared if it already exists.

If the APPEND keyword is specified, then the file pointer is moved to the end of file just after the file is opened.

If the DIRECT keyword is specified, the input-output are not buffered.

If the WATCH keyword is specified, the file is watched by the interpreter :

If the BIG or LITTLE keyword is specified, then all subsequent READ and WRITE operations on this file will use big-endian or little-endian data representation.

The variable receives the object that represents the opened stream.


Example

' Watching a serial port

DIM hFile AS File

OPEN "/dev/ttyS0" FOR READ WRITE WATCH AS #hFile

...

PUBLIC SUB File_Read()

  DIM iByte AS Byte

  READ #hFile, iByte
  PRINT "Got one byte: "; iByte

END


' Reading data from a BMP file, known to use little-endian format :

DIM hFile AS File
DIM iData AS Integer

OPEN "./image.bmp" FOR READ LITTLE AS #hFile
...
READ #hFile, iData


See also

CLOSE, COPY, Eof, FLUSH, INPUT, Lof, LINE INPUT, KILL, PRINT, READ, RENAME, Seek, SEEK, WRITE


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