X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=pod%2Fperlvar.pod;h=7c61a050960724bfdf9d5c8fb4f5bafa34a7badb;hb=3dc608da20ed2bfc3a3adc9459ee35d5fa2839b3;hp=f39ac7da2cb25a83fc21455ef96db3b2933c87ae;hpb=803059618a6e90fb614193e8cdf81c79f27d8764;p=p5sagit%2Fp5-mst-13.2.git

diff --git a/pod/perlvar.pod b/pod/perlvar.pod
index f39ac7d..7c61a05 100644
--- a/pod/perlvar.pod
+++ b/pod/perlvar.pod
@@ -58,14 +58,14 @@ the change may affect other modules which rely on the default values
 of the special variables that you have changed. This is one of the
 correct ways to read the whole file at once:
 
-    open my $fh, "foo" or die $!;
+    open my $fh, "<", "foo" or die $!;
     local $/; # enable localized slurp mode
     my $content = <$fh>;
     close $fh;
 
 But the following code is quite bad:
 
-    open my $fh, "foo" or die $!;
+    open my $fh, "<", "foo" or die $!;
     undef $/; # enable slurp mode
     my $content = <$fh>;
     close $fh;
@@ -81,7 +81,7 @@ inside some short C<{}> block, you should create one yourself. For
 example:
 
     my $content = '';
-    open my $fh, "foo" or die $!;
+    open my $fh, "<", "foo" or die $!;
     {
         local $/;
         $content = <$fh>;
@@ -148,18 +148,24 @@ don't use it:
 
 =item *
 
-Various unary functions, including functions like ord() and int(), as well
-as the all file tests (C<-f>, C<-d>) except for C<-t>, which defaults to
-STDIN.
+The following functions:
+
+abs, alarm, chomp, chop, chr, chroot, cos, defined, eval, exp, glob,
+hex, int, lc, lcfirst, length, log, lstat, mkdir, oct, ord, pos, print,
+quotemeta, readlink, readpipe, ref, require, reverse (in scalar context only),
+rmdir, sin, split (on its second argument), sqrt, stat, study, uc, ucfirst, 
+unlink, unpack.
 
 =item *
 
-Various list functions like print() and unlink().
+All file tests (C<-f>, C<-d>) except for C<-t>, which defaults to STDIN.
+See L<perlfunc/-X>
+
 
 =item *
 
-The pattern matching operations C<m//>, C<s///>, and C<tr///> when used
-without an C<=~> operator.
+The pattern matching operations C<m//>, C<s///> and C<tr///> (aka C<y///>)
+when used without an C<=~> operator.
 
 =item *
 
@@ -172,6 +178,10 @@ The implicit iterator variable in the grep() and map() functions.
 
 =item *
 
+The implicit variable of given().
+
+=item *
+
 The default place to put an input record when a C<< <FH> >>
 operation's result is tested by itself as the sole criterion of a C<while>
 test.  Outside a C<while> test, this will not happen.
@@ -181,7 +191,7 @@ test.  Outside a C<while> test, this will not happen.
 As C<$_> is a global variable, this may lead in some cases to unwanted
 side-effects.  As of perl 5.9.1, you can now use a lexical version of
 C<$_> by declaring it in a file or in a block with C<my>.  Moreover,
-declaring C<our $> restores the global C<$_> in the current scope.
+declaring C<our $_> restores the global C<$_> in the current scope.
 
 (Mnemonic: underline is understood in certain operations.)
 
@@ -231,7 +241,7 @@ See L</@-> for a replacement.
 =item ${^MATCH}
 X<${^MATCH}>
 
-This is similar to C<$&> (C<$POSTMATCH>) except that it does not incur the
+This is similar to C<$&> (C<$MATCH>) except that it does not incur the
 performance penalty associated with that variable, and is only guaranteed
 to return a defined value when the pattern was compiled or executed with
 the C</p> modifier.
@@ -302,6 +312,8 @@ matched. For example:
 (Mnemonic: be positive and forward looking.)
 This variable is read-only and dynamically scoped to the current BLOCK.
 
+=item $LAST_SUBMATCH_RESULT
+
 =item $^N
 X<$^N>
 
@@ -337,6 +349,8 @@ past where $2 ends, and so on.  You can use C<$#+> to determine
 how many subgroups were in the last successful match.  See the
 examples given for the C<@-> variable.
 
+=item %LAST_PAREN_MATCH
+
 =item %+
 X<%+>
 
@@ -431,7 +445,7 @@ instead of lines, with the maximum record size being the referenced
 integer.  So this:
 
     local $/ = \32768; # or \"32768", or \$var_containing_32768
-    open my $fh, $myfile or die $!;
+    open my $fh, "<", $myfile or die $!;
     local $_ = <$fh>;
 
 will read a record of no more than 32768 bytes from FILE.  If you're
@@ -467,7 +481,8 @@ buffered otherwise.  Setting this variable is useful primarily when
 you are outputting to a pipe or socket, such as when you are running
 a Perl program under B<rsh> and want to see the output as it's
 happening.  This has no effect on input buffering.  See L<perlfunc/getc>
-for that.  (Mnemonic: when you want your pipes to be piping hot.)
+for that.  See L<perldoc/select> on how to select the output channel. 
+See also L<IO::Handle>. (Mnemonic: when you want your pipes to be piping hot.)
 
 =item IO::Handle->output_field_separator EXPR
 
@@ -764,8 +779,7 @@ X<$^ENCODING>
 The I<object reference> to the Encode object that is used to convert
 the source code to Unicode.  Thanks to this variable your perl script
 does not have to be written in UTF-8.  Default is I<undef>.  The direct
-manipulation of this variable is highly discouraged.  See L<encoding>
-for more details.
+manipulation of this variable is highly discouraged.
 
 =item $OS_ERROR
 
@@ -779,7 +793,7 @@ variable, or in other words, if a system or library call fails, it
 sets this variable.  This means that the value of C<$!> is meaningful
 only I<immediately> after a B<failure>:
 
-    if (open(FH, $filename)) {
+    if (open my $fh, "<", $filename) {
 	# Here $! is meaningless.
 	...
     } else {
@@ -802,6 +816,10 @@ went bang?)
 
 Also see L<Error Indicators>.
 
+=item %OS_ERROR
+
+=item %ERRNO
+
 =item %!
 X<%!>
 
@@ -926,7 +944,9 @@ the same as the first number.
 
 However, a value assigned to C<$(> must be a single number used to
 set the real gid.  So the value given by C<$(> should I<not> be assigned
-back to C<$(> without being forced numeric, such as by adding zero.
+back to C<$(> without being forced numeric, such as by adding zero. Note
+that this is different to the effective gid (C<$)>) which does take a
+list.
 
 You can change both the real gid and the effective gid at the same
 time by using POSIX::setgid().  Changes to $( require a check to $!
@@ -1003,6 +1023,9 @@ to ps(1) (assuming the operating system plays along).  Note that
 the view of C<$0> the other threads have will not change since they
 have their own copies of it.
 
+If the program has been given to perl via the switches C<-e> or C<-E>,
+C<$0> will contain the string C<"-e">.
+
 =item $[
 X<$[>
 
@@ -1014,8 +1037,9 @@ subscripting and when evaluating the index() and substr() functions.
 
 As of release 5 of Perl, assignment to C<$[> is treated as a compiler
 directive, and cannot influence the behavior of any other file.
-(That's why you can only assign compile-time constants to it.)
-Its use is highly discouraged.
+(That's why you can only assign compile-time constants to it.)  Its
+use is deprecated, and will trigger a warning (if the deprecation
+L<warnings> category is enabled.  You did C<use warnings>, right?)
 
 Note that, unlike other compile-time directives (such as L<strict>),
 assignment to C<$[> can be seen from outer lexical scopes in the same file.
@@ -1047,7 +1071,7 @@ X<$^C> X<$COMPILING>
 The current value of the flag associated with the B<-c> switch.
 Mainly of use with B<-MO=...> to allow code to alter its behavior
 when being compiled, such as for example to AUTOLOAD at compile
-time rather than normal, deferred loading.  See L<perlcc>.  Setting
+time rather than normal, deferred loading.  Setting
 C<$^C = 1> is similar to calling C<B::minus_c>.
 
 =item $DEBUGGING
@@ -1199,7 +1223,8 @@ Debug subroutine enter/exit.
 
 =item 0x02
 
-Line-by-line debugging.
+Line-by-line debugging. Causes DB::DB() subroutine to be called for each
+statement executed. Also causes saving source code lines (like 0x400).
 
 =item 0x04
 
@@ -1236,12 +1261,13 @@ were compiled.
 
 =item 0x400
 
-Debug assertion subroutines enter/exit.
+Save source code lines into C<@{"_<$filename"}>.
 
 =back
 
 Some bits may be relevant at compile-time only, some at
 run-time only.  This is a new mechanism and the details may change.
+See also L<perldebguts>.
 
 =item $LAST_REGEXP_CODE_RESULT
 
@@ -1307,15 +1333,12 @@ switch); see L<perlrun> for more info on this.
 X<$^V> X<$PERL_VERSION>
 
 The revision, version, and subversion of the Perl interpreter, represented
-as a string composed of characters with those ordinals.  Thus in Perl v5.6.0
-it equals C<chr(5) . chr(6) . chr(0)> and will return true for
-C<$^V eq v5.6.0>.  Note that the characters in this string value can
-potentially be greater than 255.
+as a C<version> object.
 
 This variable first appeared in perl 5.6.0; earlier versions of perl will
-see an undefined value.
+see an undefined value. Before perl 5.10.0 $^V was represented as a v-string.
 
-This can be used to determine whether the Perl interpreter executing a
+$^V can be used to determine whether the Perl interpreter executing a
 script is in the right range of versions.  (Mnemonic: use ^V for Version
 Control.)  Example: