Open a connection to a file on a virtual ADF device

Open a connection to a file on a virtual ADF device. The created connection (if valid) should be accepted by any R function that reads from or writes to a connection, such as readLines(), writeLines(), readBin(), writeBin(), etc.

Usage

adf_file_con(x, ..., writable = FALSE)

# S3 method for class 'adf_device'
adf_file_con(x, path, ..., writable = FALSE)

# S3 method for class 'character'
adf_file_con.adf_device(x, path, ..., writable = FALSE)

# S3 method for class 'virtual_path'
adf_file_con(x, ..., writable = FALSE)

Arguments

x

Either a connection to a virtual ADF device created with connect_adf(), or a virtual_path created with virtual_path().

...

Ignored.

writable

A logical value. When TRUE the connection can be used to write to the file on the virtual device. When FALSE it can only be used to read. Note that a writeable connection can only be setup on a virtual device that is not write protected.

path

Only required when x is a virtual device of class adf_device. In that case path should be a character string representing the path to the file on the virtual device. See also vignette("virtual_paths").

Value

Returns an R connection that can be handled by any function that accepts a connection for reading or writing. Remember to call close() after use.

Author

Pepijn de Vries

Examples

## First setup a connection to a virtual device
adz_file <- system.file("example.adz", package = "adfExplorer2")
my_device <- connect_adf(adz_file)

## Open a connection to a file on the virtual device
fcon <- adf_file_con(my_device, "DF0:s/startup-sequence")

## Read from the file
my_startup <- readLines(fcon, warn = FALSE)

## Close the file
close(fcon)

## Close the virtual device
close(my_device)