[Overview][Constants][Types][Classes][Procedures and functions][Variables][Index] | Reference for unit 'sysutils' (#rtl)

# FileOpen

Open an existing file and return a filehandle

## Declaration

Source position: filutilh.inc line 74

`function FileOpen(`
`const FileName: String;`
`Mode: Integer`
`):THandle;`

## Description

FileOpen opens a file with name FileName with mode Mode. Mode can be one of the following constants:

fmOpenRead
  The file is opened for reading.
fmOpenWrite
  The file is opened for writing.
fmOpenReadWrite
  The file is opened for reading and writing.

If the file has been successfully opened, it can be read from or written to (depending on the Mode parameter) with the FileRead and FileWrite functions.

Remark: | Remark that you cannot open a file if it doesn't exist yet, i.e. it will not be created for you. If you want tp create a new file, or overwrite an old one, use the FileCreate function.

For an example, see FileOpen

## Errors

On Error, -1 is returned.

## See also

FileClose |  | Close a file handle.
FileWrite |  | Write data from a buffer to a given filehandle.
FileCreate |  | Create a new file and return a handle to it.
FileRead |  | Read data from a filehandle in a buffer.
FileTruncate |  | Truncate an open file to a given size.
FileSeek |  | Set the current file position on a file handle.

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