XLISP write-char

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# write-char

Type: | - | function (subr)
Source: | - | xlfio.c

## Syntax

(write-char char-expr [dest])
  char-expr - a character expression
  dest - an optional destination, must be a file pointer or stream, default is *standard-output*
  returns - the character

## Description

The 'write-char' function writes the 'char-expr' to the specified 'destination'. Only the 'char-expr' is written. The 'char-expr' must be a character expression. The 'char-expr' is returned as the result. The 'destination' may be a file pointer or a stream. If there is no 'destination', *standard-output* is the default.

## Examples

    (write-char #\C)                         ; prints  C

    (setq fp (open "t" :direction :output))  ; create file
    (write-char #\A fp)                      ; returns #\A
    (write-char #\B fp)                      ; returns #\B
    (write-char #\Newline fp)                ; returns #\Newline
    (close fp)                               ; returns NIL

    (read (open "t" :direction :input))      ; returns AB

Common Lisp: Common Lisp specifies that print operations with a 'destination' of NIL will go to *standard-output*. XLISP does not send the output to *standard-output* with a 'destination' of NIL. Common Lisp also specifies that a 'destination' of T will be sent to *terminal-io*, which is not defined in XLISP by default. XLISP does not allow T as a valid argument for 'destination'.

See the write-char function in the XLISP 2.0 manual.

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Nyquist / XLISP 2.0 - Contents | Tutorials | Examples | Reference