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[perl5.git] / pod / perlfunc.pod

diff --git a/pod/perlfunc.pod b/pod/perlfunc.pod
index 2169a44..776aaf2 100644 (file)
--- a/pod/perlfunc.pod
+++ b/pod/perlfunc.pod
@@ -1234,6 +1234,10 @@ lookup:
     delete $ref->[$x][$y][$index];
     delete @{$ref->[$x][$y]}[$index1, $index2, @moreindices];
 
+The C<delete local EXPR> construct can also be used to localize the deletion
+of array/hash elements to the current block.
+See L<perlsub/"Localized deletion of elements of composite types">.
+
 =item die LIST
 X<die> X<throw> X<exception> X<raise> X<$@> X<abort>
 
@@ -2631,11 +2635,13 @@ the super-user).  This is a useful way to check that a child process is
 alive (even if only as a zombie) and hasn't changed its UID.  See
 L<perlport> for notes on the portability of this construct.
 
-Unlike in the shell, if SIGNAL is negative, it kills
-process groups instead of processes.  (On System V, a negative I<PROCESS>
-number will also kill process groups, but that's not portable.)  That
-means you usually want to use positive not negative signals.  You may also
-use a signal name in quotes.
+Unlike in the shell, if SIGNAL is negative, it kills process groups instead
+of processes. That means you usually want to use positive not negative signals.
+You may also use a signal name in quotes.
+
+The behavior of kill when a I<PROCESS> number is zero or negative depends on
+the operating system.  For example, on POSIX-conforming systems, zero will
+signal the current process group and -1 will signal all processes.
 
 See L<perlipc/"Signals"> for more details.
 
@@ -2734,6 +2740,10 @@ block, file, or eval.  If more than one value is listed, the list must
 be placed in parentheses.  See L<perlsub/"Temporary Values via local()">
 for details, including issues with tied arrays and hashes.
 
+The C<delete local EXPR> construct can also be used to localize the deletion
+of array/hash elements to the current block.
+See L<perlsub/"Localized deletion of elements of composite types">.
+
 =item localtime EXPR
 X<localtime> X<ctime>
 
@@ -4073,8 +4083,6 @@ The same template may generally also be used in unpack().
 =item package NAMESPACE
 X<package> X<module> X<namespace>
 
-=item package
-
 Declares the compilation unit as being in the given namespace.  The scope
 of the package declaration is from the declaration itself through the end
 of the enclosing block, file, or eval (the same as the C<my> operator).
@@ -5365,27 +5373,26 @@ Examples:
     use sort '_mergesort';  # note discouraging _
     @new = sort { substr($a, 3, 5) cmp substr($b, 3, 5) } @old;
 
+Warning: syntactical care is required when sorting the list returned from
+a function. If you want to sort the list returned by the function call
+C<find_records(@key)>, you can use:
 
-Warning: Care is required when sorting the list returned from a function.
-
-If you want to sort returned by the function call: find_records(@key) then
-you can use:
     @contact = sort { $a cmp $b } find_records @key;
     @contact = sort +find_records(@key);
     @contact = sort &find_records(@key);
     @contact = sort(find_records(@key));
 
 If instead you want to sort the array @key with the comparison routine
-find_records then you can use:
+C<find_records()> then you can use:
+
     @contact = sort { find_records() } @key;
     @contact = sort find_records(@key);
     @contact = sort(find_records @key);
     @contact = sort(find_records (@key));
 
-
 If you're using strict, you I<must not> declare $a
 and $b as lexicals.  They are package globals.  That means
-if you're in the C<main> package and type
+that if you're in the C<main> package and type
 
     @articles = sort {$b <=> $a} @files;
 
@@ -5464,9 +5471,7 @@ Splits the string EXPR into a list of strings and returns that list.  By
 default, empty leading fields are preserved, and empty trailing ones are
 deleted.  (If all fields are empty, they are considered to be trailing.)
 
-In scalar context, returns the number of fields found and splits into
-the C<@_> array.  Use of split in scalar context is deprecated, however,
-because it clobbers your subroutine arguments.
+In scalar context, returns the number of fields found.
 
 If EXPR is omitted, splits the C<$_> string.  If PATTERN is also omitted,
 splits on whitespace (after skipping any leading whitespace).  Anything
@@ -6465,6 +6470,9 @@ C<qx//>, as described in L<perlop/"`STRING`">.  Return value of -1
 indicates a failure to start the program or an error of the wait(2) system
 call (inspect $! for the reason).
 
+If you'd like to make C<system> (and many other bits of Perl) die on error,
+have a look at the L<autodie> pragma.
+
 Like C<exec>, C<system> allows you to lie to a program about its name if
 you use the C<system PROGRAM LIST> syntax.  Again, see L</exec>.
 
@@ -6477,8 +6485,8 @@ value.
     system(@args) == 0
         or die "system @args failed: $?"
 
-You can check all the failure possibilities by inspecting
-C<$?> like this:
+If you'd like to manually inspect C<system>'s failure, you can check all
+possible failure modes by inspecting C<$?> like this:
 
     if ($? == -1) {
        print "failed to execute: $!\n";
@@ -6948,6 +6956,9 @@ C<use>ing library modules that won't work with older versions of Perl.
 Also, if the specified perl version is greater than or equal to 5.9.5,
 C<use VERSION> will also load the C<feature> pragma and enable all
 features available in the requested version.  See L<feature>.
+Similarly, if the specified perl version is greater than or equal to
+5.11.0, strictures are enabled lexically as with C<use strict> (except
+that the F<strict.pm> file is not actually loaded).
 
 The C<BEGIN> forces the C<require> and C<import> to happen at compile time.  The
 C<require> makes sure the module is loaded into memory if it hasn't been