Telnet Data Entry Terminal option(4)

　　IAC SB DET READ CURSOR IAC SE subcommand code: 17

　　This subcommand requests the receiver to send the present position　of the cursor to the sender.

　　IAC SB DET CURSOR POSITION IAC SE subcommand code: 18　where and are positive 8-bit binary integers.

　　This subcommand is sent by a Telnet implementation in response to a　READ CURSOR subcommand to convey the coordinates of the cursor to　the other side. Note: x is less than M and y is less than N.

　　IAC SB DET REVERSE TAB IAC SE subcommand code: 19

　　This subcommand causes the cursor to move to the previous tab　position. If none exists on the present line, the cursor moves to　the previous line and so on until a tab is found or the address　(0,0) is encountered. When field protection is in effect the cursor　moves to the beginning of the preceding unprotected field.

　　Transmit Functions (For detailed semantics see Section 5.)

　　IAC SB DET TRANSMIT SCREEN IAC SE subcommand code: 20

　　This subcommand causes the terminal to transmit all characters on　the screen from position (0,0) to (M-1,N-1). The cursor will be at　(0,0) after the operation is complete.

　　IAC SB DET TRANSMIT UNPROTECTED IAC SE subcommand code: 21

　　This subcommand causes the terminal to transmit all characters in　unprotected fields from position (0,0) to (M-1,N-1). The unprotected　fields are separated by the field separator subcommand. The cursor　will be at (0,0) or at the beginning of the first unprotected field　after the operation is complete.

　　IAC SB DET TRANSMIT LINE IAC SE subcommand code: 22

　　This subcommand causes the terminal to transmit all data on the yth　line where y is determined by the present position of the cursor.

　　Data is sent from character position (0,y) to the end-of-line or　position (M-1,y) whichever comes first. The cursor position after　the transmission is one character position after the end of line　condition or the beginning of the next line, (0,y+1).

　　IAC SB DET TRANSMIT FIELD IAC SE subcommand code: 23

　　This subcommand causes the terminal to transmit all data in the　field presently occupied by the cursor. The cursor position after　the operation is complete is one character position after the end of　the field or, if that　position is protected, at the beginning of the next unprotected　field.

　　IAC SB DET TRANSMIT REST OF SCREEN IAC SE subcommand code: 24

　　This subcommand causes the terminal to transmit all characters on　the screen from position (x,y) to (M-1,N-1) or until the end of　text. (x,y) is the current cursor position. The cursor position　after the operation is one character position after the last text　character, or (0,0) if the last filled character position is　(M-1,N-1).

　　IAC SB DET TRANSMIT REST OF LINE IAC SE subcommand code: 25

　　This subcommand causes the terminal to transmit all characters on　the yth line from position (x,y) to the end of line or (M-1,y)　whichever comes first. (x,y) is the current cursor position. The　cursor position after the operation is one character position after　the last character of the line or the first character of the next　line.

　　IAC SB DET TRANSMIT REST OF FIELD IAC SE subcommand code: 26

　　This subcommand causes the receiver to transmit the rest of the　characters in the field currently occupied by the cursor. The cursor　position after the operation is at the beginning of the next field.

　　IAC SB DET TRANSMIT MODIFIED IAC SE subcommand code: 27

　　This subcommand causes the receiver to transmit only those fields　which have the modified attribute set. The cursor position after the　operation is unchanged.

　　IAC SB DET DATA TRANSMIT IAC SE subcommand code: 28

　　This subcommand is used to preface data sent from the terminal in　response to a user action or a TRANSMIT command. The parameters 　and indicate the initial position of the cursor. See the　Transmit Subcommands subsection in Section 5 for more details. A　DATA TRANSMIT subcommand may precede an entire transmission with　each field being delineated by the FIELD SEPARATOR subcommand as　would be the case in a response toa　TRANSMIT UNPROTECTED. Or, it may precede each field as would be the　case in a response to a TRANSMIT MODIFIED.

　　Erase Functions

　　IAC SB DET ERASE SCREEN IAC SE subcommand code: 29

　　This subcommand causes all characters to be removed from the screen.