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# Copyright(c) 1986 Association of Universities for Research in Astronomy Inc.
include <mach.h>
include <config.h>
include "ki.h"
# KT_ZNOT -- Note the file position of a text device. We are called only if
# the device does not reside on the local node.
procedure kt_znot (device, chan, loffset)
int device # device driver code
int chan # channel assigned device
long loffset # receives the file offset
pointer bd, rp
int server, status
int ki_sendrcv()
long ki_decode()
include "kichan.com"
include "kii.com"
define physnote_ 91
begin
bd = k_bufp[chan]
# The buffering of text file input and output complicates the seek and
# note functions. Our solution is [1] for an output file, flush the
# output and then call the kernel server to note the file position, and
# [2] for an input file, have the kernel server note the offset of each
# input line of text in the header area of each input record.
if (B_ITOP(bd) >= B_BUFPTR(bd)) {
# Input file.
rp = B_RP(bd)
# Check for end of input buffer.
if (rp >= B_ITOP(bd))
goto physnote_
# If already part way into line, return offset of the next line.
if (B_CI(bd) > 0) {
rp = rp + ki_decode (R_RECLEN(rp), NCHARS_INT)
if (rp >= B_ITOP(bd))
goto physnote_
}
# Decode seek offset from record header of next line to be
# read. The seek offset is encoded as a char sequence.
loffset = ki_decode (R_SEKOFF(rp), NCHARS_LONG)
return
} else {
# Output file.
call ki_flushtx (device, chan, status)
if (status == ERR)
return
}
physnote_
# Physically call the kernel server to note the file offset.
server = k_node[chan]
p_arg[1] = k_oschan[chan]
if (ki_sendrcv (server, device, TX_NOT) == ERR)
loffset = ERR
else
loffset = ki_decode (p_sbuf, NCHARS_LONG)
end
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