[net.news.sa] New news batching/compression scheme

stephen@dcl-cs.UUCP (Stephen J. Muir) (09/09/85)

In article <735@mcvax.UUCP> piet@mcvax.UUCP (Piet Beertema) writes:
>A while ago we've switched to a new news batching/compression scheme on
>the mcvax-seismo link and a number of other links. That is working highly
>satisfactorily now. Even with the necessary expansion for uucp's f-proto
>the data reduction is some 30%. If you're not using the f-proto on certain
>links, you can also use compression without subsequent encoding (see below,
>sendbatch) and get a reduction of over 40%.
>Here's the stuff; the compress source is contained in it, so if you're just
>interested in that, extract it.

1) the "sendbatch" script doesn't keep a complete log if news is being batched
   and received at the same time.  Also, it's nice to put the date in the log.

*** sendbatch.sh.orig	Sun Sep  8 22:53:30 1985
--- sendbatch.sh	Sun Sep  8 23:55:37 1985
***************
*** 24,34
  	-*c*)	compr=$rmt; continue;;
  	esac
  
- 	# keep a temporary backup; o.file should be removed regularly
- 	if test -s $BDIR/$rmt
- 	then
- 		cat $BDIR/$rmt >> $BDIR/o.$rmt
- 	fi
  	while test $? -eq 0 -a \( -s $BDIR/$rmt -o -s $BDIR/$rmt.work \)
  	do
  		case $compr in

--- 24,29 -----
  	-*c*)	compr=$rmt; continue;;
  	esac
  
  	while test $? -eq 0 -a \( -s $BDIR/$rmt -o -s $BDIR/$rmt.work \)
  	do
  
***************
*** 31,36
  	fi
  	while test $? -eq 0 -a \( -s $BDIR/$rmt -o -s $BDIR/$rmt.work \)
  	do
  		case $compr in
  		# compression + 7-bit
  		-c7)

--- 26,39 -----
  
  	while test $? -eq 0 -a \( -s $BDIR/$rmt -o -s $BDIR/$rmt.work \)
  	do
+ 
+ 		# keep a temporary backup; file.log should be removed regularly
+ 		if test -s $BDIR/$rmt -a ! -s $BDIR/$rmt.work
+ 		then
+ 			date >> $BDIR/$rmt.log
+ 			cat $BDIR/$rmt >> $BDIR/$rmt.log
+ 		fi
+ 
  		case $compr in
  		# compression + 7-bit
  		-c7)

2) The following comment in file "batch.c" is not true: the '\n' character in
   variable "fname" in file "batch.c" has been replaced by a '\0'.

			/* breaking out of this early will end up resyncing
			   the batch files (isn't serendipity wonderful?) */
-- 
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