The TYPE command -- Set File Transmission Type

  The server keeps track of a binary flag for the client. At any moment, the binary flag is either on or off. At the beginning of the FTP connection, the binary flag is off.

While the binary flag is on, all RETR, STOR, APPE, and STOU requests are for binary files. While the binary flag is off, all RETR, STOR, APPE, and STOU requests are for text files. The binary flag has no effect on NLST and LIST.

A TYPE request controls the binary flag. It has a parameter. There are four possibilities for the parameter:

A

-- Turn the binary flag off.

A N

-- Turn the binary flag off.

I

-- Turn the binary flag on.

L 8

-- Turn the binary flag on.

The server accepts the TYPE request with code 200.