X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2Flook.pl;h=ccc9b6162ae0f8885f316b854f48c2fdc4c3bd54;hb=e323741737633027a4605d074649eee3af027cf2;hp=ebbaa73a3d61d613becdd7426fa1c6d713b87413;hpb=a687059cbaf2c6fdccb5e0fae2aee80ec15625a8;p=p5sagit%2Fp5-mst-13.2.git

diff --git a/lib/look.pl b/lib/look.pl
index ebbaa73..ccc9b61 100644
--- a/lib/look.pl
+++ b/lib/look.pl
@@ -1,27 +1,31 @@
 ;# Usage: &look(*FILEHANDLE,$key,$dict,$fold)
-
+#
+# This library is no longer being maintained, and is included for backward
+# compatibility with Perl 4 programs which may require it.
+#
+# In particular, this should not be used as an example of modern Perl
+# programming techniques.
+#
 ;# Sets file position in FILEHANDLE to be first line greater than or equal
 ;# (stringwise) to $key.  Pass flags for dictionary order and case folding.
 
 sub look {
-    local(*FH,$key,$fold) = @_;
+    local(*FH,$key,$dict,$fold) = @_;
     local($max,$min,$mid,$_);
     local($dev,$ino,$mode,$nlink,$uid,$gid,$rdev,$size,$atime,$mtime,$ctime,
        $blksize,$blocks) = stat(FH);
     $blksize = 8192 unless $blksize;
     $key =~ s/[^\w\s]//g if $dict;
-    $key =~ y/A-Z/a-z/ if $fold;
-    $max = $size + $blksize - 1;
-    $max -= $size % $blksize;
-    while ($max - $min > $blksize) {
-	$mid = ($max + $min) / 2;
-	die "look: internal error"  if $mid % $blksize;
-	seek(FH,$mid,0);
-	$_ = <FH>;		# probably a partial line
+    $key = lc $key if $fold;
+    $max = int($size / $blksize);
+    while ($max - $min > 1) {
+	$mid = int(($max + $min) / 2);
+	seek(FH,$mid * $blksize,0);
+	$_ = <FH> if $mid;		# probably a partial line
 	$_ = <FH>;
 	chop;
 	s/[^\w\s]//g if $dict;
-	y/A-Z/a-z/ if $fold;
+	$_ = lc $_ if $fold;
 	if ($_ lt $key) {
 	    $min = $mid;
 	}
@@ -29,11 +33,13 @@ sub look {
 	    $max = $mid;
 	}
     }
+    $min *= $blksize;
     seek(FH,$min,0);
+    <FH> if $min;
     while (<FH>) {
 	chop;
 	s/[^\w\s]//g if $dict;
-	y/A-Z/a-z/ if $fold;
+	$_ = lc $_ if $fold;
 	last if $_ ge $key;
 	$min = tell(FH);
     }