GNU screen

screen is flexible about flow control. Traditionally, some terminals do flow control in-band, using ^S when they want to stop the flow data and ^Q when they want it to resume. On the other hand, some programs (such as emacs) use those keys for other purposes. If flow control is turned on in screen, ^S will stop screen from sending anything more to your terminal and ^Q will resume. Turning flow control off allows those characters to pass through to your programs. The default setting is “auto”, which attempts to determine if flow control is needed or not. screen is generally pretty good at figuring this out.

• -a - “include all capabilities (with some minor exceptions) in each window's termcap, even if screen must redraw parts of the display in order to implement a function.”
• -A - Resize windows to fit the current terminal. Only effective if screen would otherwise try to resize your terminal to fit the windows.
• -f, -fn, -fa - Respectively, set flow control on, off, or automatic. Same as defflow.
• -O - “selects a more optimal output mode for your terminal rather than true VT100 emulation (only affects auto-margin terminals without 'LP'). This can also be set in your .screenrc by specifying 'OP' in a termcap command.”
• -U - Run screen in UTF-8 mode. screen assumes that it can output UTF-8 (normally it checks locale settings) and sets defutf8 on.

• C-a C-b - (break) Sends a break signal to the current window.
• C-a B - (pow_break) Closes and reopens the terminal and sends a break signal.
• C-a f - (flow) Toggle flow setting between on, off, and auto.
• C-a q - (xon) Sends an XON (^Q) to the current window.
• C-a r - (wrap) Toggle the current window's line-wrap setting.
• C-a S - (xoff) Sends an XOFF (^S) to the current window.
• C-a W - (width) Toggle terminal between 80 and 132 columns.
• C-a Z - (reset) Reset the window's terminal settings to its defaults.
• C-a . - (dumptermcap) Write out a .termcap file.

terminal (allpartial, altscreen, bce, c1, charset, defbce, defbreaktype, defc1, defcharset, defflow, defgr, defencoding, defnonblock, defutf8, defwrap, dumptermcap, encoding, flow, gr, nonblock, dinfo, partial, printcmd, reset, term, termcap, terminfo, termcapinfo, utf8, wrap, zmodem)