| Open Statement |
Named Arguments
No
Syntax
Open pathname For mode [Access access] [lock] As [#]filenumber
[Len=reclength]
pathname
Use: Required
Data Type: String
The name of the file to open, along with an optional path.
mode
Use: Required
Data Type: Keyword
The file access mode: append, binary, input, output, or random.
access
Use: Optional
Data Type: Keyword
Specifies the allowable operations by the current process.
lock
Use: Optional
Type: Keyword
Specifies the allowable operations by other processes.
filenumber
Use: Required
Data Type: Integer
A valid file number between 1 and 511.
reclength
Use: Optional
Data Type: Integer
The length of the record or I/O buffer.
Description
Before reading from and/or writing to a disk file, you must first open the file using the Open statement. The Open statement allocates memory for the I/O buffer and optionally sets access locks on the file.
Rules at a Glance
pathname may include the directory or folder and drive; if these are omitted, the file is assumed to reside in the current working directory. If pathname does include drive and path information, this may take the form of a path relative to the local system or a UNC path.
The default mode for opening a disk file (when mode isn't specified) is random.
If the specified file doesn't exist when opening in input mode, an error occurs.
A new file is created if the specified file doesn't exist when opening in append, binary, output, or random mode.
access allows you to restrict the actions ...
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