27  Input/Output Functions

1. get-key - get a single key stroke from the keyboard
2. read - read an expression
3. print - print an expression on a new line
4. prin1 - print an expression
5. princ - print an expression without quoting
6. pprint - pretty print an expression
7. terpri - terminate the current print line
8. flatsize - length of printed representation using prin1
9. flatc - length of printed representation using princ

(get-key) - get a single key stroke from the keyboard

returns - the decimal ASCII value of the key pressed
Note: this function is not supported on all systems

(read [stream [eof [rflag]]]) - read an expression

stream - the input stream [default is standard input]
eof - the value to return on end of file [default is NIL]
rflag - recursive read flag [default is NIL]
returns - the expression read

(print expr [stream]) - print an expression on a new line

expr - the expression to be printed
stream - the output stream [default is standard output]
returns - the expression

(prin1 expr [stream]) - print an expression

expr - the expression to be printed
stream - the output stream [default is standard output]
returns - the expression

(princ expr [stream]) - print an expression without quoting

expr - the expressions to be printed
stream - the output stream [default is standard output]
returns - the expression

(pprint expr [stream]) - pretty print an expression

expr - the expressions to be printed
stream - the output stream [default is standard output]
returns - always returns NIL

(terpri [stream]) - terminate the current print line

stream - the output stream [default is standard output]
returns - NIL

(flatsize expr) - length of printed representation using prin1

expr - the expression
returns - the length

(flatc expr) - length of printed representation using princ

expr - the expression
returns - the length