21. LINE_FEED

*------------------------------------------------------------------------------
* NAME          LINE_FEED
*------------------------------------------------------------------------------
* DEPENDENCY    None
* PURPOSE       To send a linefeed character to the channel in A0.
* DESCRIPTION   This routine prints a linefeed character to the channel ID
*               passed in A0.
* INPUTS :
*               A0.L = Channel ID
* OUTPUTS :
*               D0 = Error code
*               A0 = Channel id (preserved)
*               Z flag set if no errors, unset otherwise.
*------------------------------------------------------------------------------
line_feed       movem.l d1/a1,-(a7)     ; Preserve any registers reqd
                moveq   #io_sbyte,d0    ; Send one byte to channel
                moveq   #linefeed,d1    ; Byte to send = linefeed
                moveq   #infinite,d3    ; Timeout
                trap    #3              ; Do it
                movem.l (a7)+,d1/a1     ; Restore
                tst.l   d0              ; Set Z if errors
                rts