mkfile to build printarena by default, dumpvacroots to pick up $venti,
makes retreiving lost vac scores less hassle when disks die.

Notes:
Mon Feb 13 09:00:33 EST 2006 rsc

Reference: /n/sources/patch/applied/venti-printarenas
Date: Mon Feb 13 11:14:32 CET 2006
Reviewed-by: rsc

--- /sys/src/cmd/venti/mkfile	Mon Feb 13 11:11:14 2006
+++ /sys/src/cmd/venti/mkfile	Mon Feb 13 11:11:10 2006
@@ -63,6 +63,7 @@
 	write\
 	copy\
 	conf\
+	printarena\
 #	dumparena\
 
 CFILES=${TARG:%=%.c} $LIBCFILES
--- /sys/src/cmd/venti/dumpvacroots	Mon Feb 13 11:11:31 2006
+++ /sys/src/cmd/venti/dumpvacroots	Mon Feb 13 11:11:28 2006
@@ -4,11 +4,12 @@
 # if nothing else, this illustrates that you have to control access
 # to the physical disks storing the archive!
 
-ventihttp=your-server:8000
+ventihttp=`{echo $venti | sed 's/^[a-z]+!([0-9\.]+)![a-z0-9]+$/\1/; s/^[a-z]+!([0-9\.]+)/\1/; s/$/:8000/'}
+
 hget http://$ventihttp/index | 
 awk '
  /^index=/ { blockSize=0+substr($3, 11); }
  /^arena=/ { arena=substr($1, 7); }
- /^	arena=/ { start=0+substr($5, 2)-blockSize; printf("./8.printarena -o %d %s\n", start, $3); }' |
+ /^	arena=/ { start=0+substr($5, 2)-blockSize; printf("venti/printarena -o %d %s\n", start, $3); }' |
 rc |
 sed -n 's/^(.*) 1$/vac:\1/p'