ref: edec6e6a70d7df83a5c5f3c19d240e72d38a6c55
dir: /rc/bin/yesterday/
#!/bin/rc rfork e smon='s/Jan/01/ s/Feb/02/ s/Mar/03/ s/Apr/04/ s/May/05/ s/Jun/06/ s/Jul/07/ s/Aug/08/ s/Sep/09/ s/Oct/10/ s/Nov/11/ s/Dec/12/' fn usage { echo 'usage: yesterday [-abcCdDs] [-[[[yy]yy]mm]dd] [-n daysago] file ...' >[1=2] exit 'usage' } fn Xcp { echo cp $1 $2 cp $1 $2 } fn Xdiff { echo diff $1 $2 diff $1 $2 } fn Xdiffn { echo diff -n $1 $2 diff -n $1 $2 } fn Xadiff { echo /acme/bin/adiff $1 $2 /acme/bin/adiff $1 $2 } fn Xcarefulcp { if(! cmp -s $1 $2) Xcp $1 $2 } fn Xecho { echo $1 } fn Xbind { echo bind $1 $2 bind $1 $2 } year=`{date|sed 's/.* //'} copy=Xecho last=() defdump=dump while(! ~ $#* 0 && ~ $1 -* && ! ~ $1 --){ switch($1){ case -a copy=Xadiff shift case -b copy=Xbind shift case -c copy=Xcp shift case -d copy=Xdiff shift case -D copy=Xdiffn shift case -C copy=Xcarefulcp shift case -s defdump=snap shift case -n* if(~ $1 -n){ if(~ $#* 1) usage shift days=$1 } if not days=`{echo $1 | sed 's/^-.//'} last=`{date `{hoc -e `{date -n} ^ '-'$days'*60*60*24'} | \ sed -e 's%... (...) (..) ..:..:.. ... (....)%\3/\1\2%' -e 'y/ /0/' -e $smon} shift case -? mon=`{date|sed -e 's/^....(...).*/\1/' -e $smon} last=$year/$mon ^`{echo $1|sed 's/^-/0/'} shift case -?? mon=`{date|sed -e 's/^....(...).*/\1/' -e $smon} last=$year/$mon ^`{echo $1|sed 's/^-//'} shift case -???? last=$year/ ^ `{echo $1|sed 's/^-//'} shift case -?????? last=`{echo $year|sed 's/..$//'} ^ `{echo $1|sed 's/^-(..)/\1\//'} shift case -???????? last=`{echo $1|sed 's/^-(....)/\1\//'} shift case * usage } } if(! ~ $#* 0 && ~ $1 --) shift if(~ $#* 0) usage dir=`{pwd} if(! ~ $status ''){ echo 'yesterday: can''t find directory' >[1=2] exit 'pwd failed' } for(i){ xpath=`{cleanname -d $dir -- $i} xdump=$defdump dumppath=$xpath if(~ $xpath /n/*/*){ xdump=`{echo $xpath | sed 's:/n/([^/]+)/.*:\1'$defdump':'} dumppath=`{echo $xpath | sed 's:/n/[^/]+(/.*):\1:'} } if(! test -e /n/$xdump/$year) 9fs $xdump if(~ $#last 0){ xlast=`{ls /n/$xdump/$year|sed -n '$p'} switch($defdump){ case snap xlast=`{ls $xlast|sed -n '$p'} } } if not xlast=/n/$xdump/$last if(! test -e $xlast){ echo 'yesterday:' \ `{echo $xlast|sed 's/.n.'$defdump'.(....).(..)(..)/\1 \2 \3/'} \ 'is not a backup day for' $xdump >[1=2] exit 'bad date' } $copy $xlast^$dumppath $xpath } exit ''