1 files changed, 118 insertions, 0 deletions
diff --git a/sys/etc/lpopen.x b/sys/etc/lpopen.x
new file mode 100644
index 00000000..4754e779
--- /dev/null
+++ b/sys/etc/lpopen.x
@@ -0,0 +1,118 @@
+# Copyright(c) 1986 Association of Universities for Research in Astronomy Inc.
+
+include	<knet.h>
+include	<mach.h>
+
+define	LP_INACTIVE	0
+define	LP_READ		1
+define	LP_WRITE	2
+define	(LPCOM,	common /lprcom/ lp_type, lp_nbytes)
+
+# LPOPEN -- Open the line printer device as a text or binary file.  If opened
+# as a text file, we arrange for the chars to be packed upon output, but in all
+# cases the printer device appears to be a streaming binary file to FIO.
+# If the printer device is opened as a binary file, the data stream is passed
+# directly on to the device without modification.  To simplify things a little
+# we permit only one printer to be open at a time; this restriction can easily
+# be removed should it prove desirable.
+
+int procedure lpopen (device, mode, type)
+
+char	device[ARB]
+int	mode, type
+
+int	fd
+int	lp_type, lp_nbytes
+bool	streq()
+int	fopnbf()
+extern	zopnlp(), lp_zaread(), lp_zawrite(), lp_zawait(), zsttlp(), zclslp()
+LPCOM
+
+begin
+	# The TEXT device is special; it has a termcap entry and is used to
+	# format text for an ASCII textfile rather than a printer.
+
+	if (streq (device, "text"))
+	    fd = STDOUT
+	else {
+	    lp_type   = type
+	    lp_nbytes = ERR
+	    fd = fopnbf (device, mode,
+		zopnlp, lp_zaread, lp_zawrite, lp_zawait, zsttlp, zclslp)
+	}
+
+	return (fd)
+end
+
+
+# LP_ZAREAD -- FIO z-aread routine for the line printer device.  FIO calls
+# us with the size of the buffer in bytes.  If the printer is opened as a
+# text file, we read a factor of SZB_CHAR less than that from the lowest
+# level, then unpack the data inplace in the FIO buffer.
+
+procedure lp_zaread (chan, buf, maxbytes, offset)
+
+int	chan
+char	buf[ARB]
+int	maxbytes
+long	offset			# ignore, since lp is streaming device
+
+int	nbytes
+int	lp_type, lp_nbytes
+LPCOM
+
+begin
+	nbytes = maxbytes
+	if (lp_type == TEXT_FILE)
+	    nbytes = nbytes / SZB_CHAR
+
+	call zardlp (chan, buf, nbytes, offset)
+	call zawtlp (chan, lp_nbytes)
+
+	if (lp_nbytes > 0 && lp_type == TEXT_FILE)
+	    call chrupk (buf, 1, buf, 1, lp_nbytes)
+end
+
+
+# LP_ZAWRITE -- FIO z-awrite routine for the line printer device.  FIO calls
+# us with the size of the buffer in bytes.  If the printer is opened as a
+# text file, we first pack the data inplace in the FIO buffer, then write it
+# out to the device.  It is ok to modify the data directly in the FIO buffer
+# since the device is a streaming device (no seeks).
+
+procedure lp_zawrite (chan, buf, nbytes, offset)
+
+int	chan
+char	buf[ARB]
+int	nbytes
+long	offset			# ignore, since lp is streaming device
+
+int	nbytes_to_write
+int	lp_type, lp_nbytes
+LPCOM
+
+begin
+	nbytes_to_write = nbytes
+	if (lp_type == TEXT_FILE) {
+	    nbytes_to_write = nbytes_to_write / SZB_CHAR
+	    call chrpak (buf, 1, buf, 1, nbytes_to_write)
+	}
+
+	call zawrlp (chan, buf, nbytes_to_write, offset)
+	call zawtlp (chan, lp_nbytes)
+end
+
+
+# LP_ZAWAIT -- Wait for i/o to the line printer to complete.  We do not bother
+# with truely asynchronous i/o for line printer devices.
+
+procedure lp_zawait (chan, nbytes)
+
+int	chan
+int	nbytes
+int	lp_type, lp_nbytes
+LPCOM
+
+begin
+	nbytes = lp_nbytes
+end