- Most terminals one encounters follow the ECMA-48 standard insofar as
- their function keys produce character sequences prefixed with the
- escape character ESC. This fact implies that <EM>curses</EM> cannot know
- whether the terminal has sent an ESC key stroke or the beginning of a
- function key's character sequence without waiting to see if, and how
- soon, further input arrives. When <EM>curses</EM> reads such an ambiguous
- character, it sets a timer. If the remainder of the sequence does not
- arrive within the designated time, <STRONG>wgetch</STRONG> returns the prefix character;
- otherwise, it returns the function key code corresponding to the unique
- sequence defined by the terminal. Consequently, a user of a <EM>curses</EM>
- application may experience a delay after pressing ESC while <EM>curses</EM>
- disambiguates the input; see section "EXTENSIONS" below. If the window
- is in "no time-out" mode, the timer does not expire; it is an infinite
- (or very large) value. See <STRONG><A HREF="notimeout.3x.html">notimeout(3x)</A></STRONG>. Because function key
- sequences usually begin with an escape character, the terminal may
- appear to hang in no time-out mode after the user has pressed ESC.
- Generally, further typing "awakens" <EM>curses</EM>.
+ Most terminals one encounters follow the ECMA-48 standard insofar as
+ their function keys produce character sequences prefixed with the
+ escape character ESC. This fact implies that <EM>curses</EM> cannot distinguish
+ a user's press of the escape key (assuming it sends ESC) from the
+ beginning of a function key's character sequence without waiting to see
+ if, and how soon, further input arrives. When <EM>curses</EM> reads such an
+ ambiguous character, it sets a timer. If the remainder of the sequence
+ does not arrive within the designated time, <STRONG>wgetch</STRONG> returns the prefix
+ character; otherwise, it returns the function key code corresponding to
+ the unique sequence defined by the terminal. Consequently, a user of a
+ <EM>curses</EM> application may experience a delay after they escape key is
+ pressed while <EM>curses</EM> disambiguates the input; see section "EXTENSIONS"
+ below. If the window is in "no time-out" mode, the timer does not
+ expire; it is an infinite (or very large) value. See <STRONG><A HREF="notimeout.3x.html">notimeout(3x)</A></STRONG>.
+ Because function key sequences usually begin with ESC, the terminal may
+ appear to hang in no time-out mode after the user presses the escape
+ key. Generally, further typing "awakens" <EM>curses</EM>.