I want to use combine keys in my code such as ctrl+w or or Alt or F
keys.What should I do? and is there any special data type which I use
for this purpose?
There's no way to do this in portable C.
Some key combinations may show up as single characters, depending on
how you read them. For example, if you read a control-w using
getchar(), you'll probably see a single '\x17' character (assuming
ASCII and the usual semantics of the control key). If you use a
lower-level interface, you might see the keystrokes separately, but
that's *extremely* system-specific.
In general, portable C can't read a single character or keystroke
without waiting for the end of the line. See question 19.1 of the
C FAQ <
http://www.eskimo.com/~scs/C-faq/top.html>.
The particular character sequences produced by particular keystrokes
(control-w, alt-f, F1, etc.) are system-specific.