TN3270(1) TN3270(1) NAME tn3270 - full-screen remote login to IBM VM/CMS SYNOPSIS tn3270 sysname DESCRIPTION _T_n_3_2_7_0 permits a full-screen, full-duplex connection from a VAX UNIX machine to an IBM machine running VM/CMS giving the appearance of being logged in directly to the remote machine on an IBM 3270 terminal. Of course you must have an account on the machine to which you wish to connect in order to log in. _T_n_3_2_7_0 looks to the user in many respects like the Yale ASCII Terminal Communication System II. _T_n_3_2_7_0 is actu‐ ally a modification of the Arpanet TELNET user interface (see _t_e_l_‐ _n_e_t(1)) that interprets and generates raw 3270 control streams. Emulation of the 3270 terminal is done in the Unix process. This emu‐ lation involves mapping 3270-style commands from the host into appro‐ priate sequences to control the user’s terminal screen. _T_n_3_2_7_0 uses _c_u_r_s_e_s(3x) and the _/_e_t_c_/_t_e_r_m_c_a_p file to do this. The emulation also involves simulating the special 3270 keyboard keys (program function keys, etc.) by mapping sequences of keystrokes from the ASCII keyboard into appropriate 3270 control strings. This mapping is terminal depen‐ dent and is specified in a description file, _/_e_t_c_/_m_a_p_3_2_7_0, (see _m_a_p_3_2_7_0(5)) or in an environment variable _M_A_P_3_2_7_0 (see _m_s_e_t(1)). Any special function keys on the ASCII keyboard are used whenever possible. If an entry for the user’s terminal is not found, _t_n_3_2_7_0 looks for an entry for the terminal type unknown. If this is not found, _t_n_3_2_7_0 uses a default keyboard mapping (see _m_a_p_3_2_7_0(5)). The first character of each special keyboard mapping sequence is either an ASCII escape (ESC), a control character, or an ASCII delete (DEL). If the user types an unrecognized function key sequence, _t_n_3_2_7_0 sends an ASCII bell (BEL), or a visual bell if defined in the user’s termcap entry, to the user’s terminal and nothing is sent to the IBM host. If _t_n_3_2_7_0 is invoked without specifying a remote host system name, it enters local command mode, indicated by the prompt ‘‘tn3270>’’. In this mode, _t_n_3_2_7_0 accepts and executes the following commands: open connect to a remote host close close the current connection quit exit tn3270 z suspend tn3270 status print connection status ? print help information Other common _t_e_l_n_e_t commands are not available in _t_n_3_2_7_0_. _T_n_3_2_7_0 com‐ mand mode may also be entered, after connecting to a host, by typing a special escape character (typically control-C). While in command mode, any host login session is still alive but tem‐ porarily suspended. The host login session may be resumed by entering an empty line (press the RETURN key) in response to the command prompt. A session may be terminated by logging off the foreign host, or by typ‐ ing ‘‘quit’’ or ‘‘close’’ while in local command mode. FILES /etc/termcap /etc/map3270 AUTHOR Greg Minshall SEE ALSO mset(1), telnet(1), termcap(3x), termcap(5), map3270(5), _Y_a_l_e _A_S_C_I_I _T_e_r_m_i_n_a_l _C_o_m_m_u_n_i_c_a_t_i_o_n _S_y_s_t_e_m _I_I _P_r_o_g_r_a_m _D_e_s_c_r_i_p_t_i_o_n_/_O_p_e_r_a_t_o_r_’_s _M_a_n_u_a_l (IBM SB30-1911) BUGS Performance is slow and uses system resources prodigiously. Not all 3270 functions are supported, nor all Yale enhancements. 4.3 Berkeley Distribution January 11, 1986 TN3270(1)