PerlIO::Via: check arg is non-NULL before using it.

[perl5.git] / pod / perlfunc.pod

diff --git a/pod/perlfunc.pod b/pod/perlfunc.pod
index 664e2a3..37046b8 100644 (file)
--- a/pod/perlfunc.pod
+++ b/pod/perlfunc.pod
@@ -1228,9 +1228,10 @@ change your current working directory, which is unaffected.)  For security
 reasons, this call is restricted to the superuser.  If FILENAME is
 omitted, does a L<C<chroot>|/chroot FILENAME> to L<C<$_>|perlvar/$_>.
 
-B<NOTE:>  It is good security practice to do C<chdir("/")>
+B<NOTE:>  It is mandatory for security to C<chdir("/")>
 (L<C<chdir>|/chdir EXPR> to the root directory) immediately after a
-L<C<chroot>|/chroot FILENAME>.
+L<C<chroot>|/chroot FILENAME>, otherwise the current working directory
+may be outside of the new root.
 
 Portability issues: L<perlport/chroot>.
 
@@ -6379,7 +6380,9 @@ C<HASH>, C<CODE>, C<FORMAT>, or C<IO>, indicating only which kind of
 object it is.  If the unblessed referent is a scalar, then the return
 value will be one of the strings C<SCALAR>, C<VSTRING>, C<REF>, C<GLOB>,
 C<LVALUE>, or C<REGEXP>, depending on the kind of value the scalar
-currently has.  Beware that these built-in type names can also be used as
+currently has.   But note that C<qr//> scalars are created already
+blessed, so C<ref qr/.../> will likely return C<Regexp>.  Beware that
+these built-in type names can also be used as
 class names, so C<ref> returning one of these names doesn't unambiguously
 indicate that the referent is of the kind to which the name refers.
 
@@ -6787,8 +6790,8 @@ X<say>
 =for Pod::Functions +say output a list to a filehandle, appending a newline
 
 Just like L<C<print>|/print FILEHANDLE LIST>, but implicitly appends a
-newline.  C<say LIST> is simply an abbreviation for
-C<{ local $\ = "\n"; print LIST }>.  To use FILEHANDLE without a LIST to
+newline at the end of the LIST instead of any value L<C<$\>|perlvar/$\>
+might have.  To use FILEHANDLE without a LIST to
 print the contents of L<C<$_>|perlvar/$_> to it, you must use a bareword
 filehandle like C<FH>, not an indirect one like C<$fh>.
 
@@ -8063,8 +8066,8 @@ as supported by the compiler used to build Perl:
    h           interpret integer as C type "short" or
                "unsigned short"
    j           interpret integer as C type "intmax_t" on Perl
-               5.14 or later; and only with a C99 compiler
-               prior to Perl 5.30 (unportable)
+               5.14 or later; and prior to Perl 5.30, only with
+               a C99 compiler (unportable)
    l           interpret integer as C type "long" or
                "unsigned long"
    q, L, or ll interpret integer as C type "long long",
@@ -8731,7 +8734,7 @@ X<sysseek> X<lseek>
 
 Sets FILEHANDLE's system position I<in bytes> using L<lseek(2)>.  FILEHANDLE may
 be an expression whose value gives the name of the filehandle.  The values
-for WHENCE are C<0> to set the new position to POSITION; C<1> to set the it
+for WHENCE are C<0> to set the new position to POSITION; C<1> to set it
 to the current position plus POSITION; and C<2> to set it to EOF plus
 POSITION, typically negative.
 
@@ -9667,10 +9670,8 @@ to try to write off the beginning of the string (i.e., negative OFFSET).
 If the string happens to be encoded as UTF-8 internally (and thus has
 the UTF8 flag set), L<C<vec>|/vec EXPR,OFFSET,BITS> tries to convert it
 to use a one-byte-per-character internal representation. However, if the
-string contains characters with values of 256 or higher, that conversion
-will fail, and a deprecation message will be raised.  In that situation,
-C<vec> will operate on the underlying buffer regardless, in its internal
-UTF-8 representation.  In Perl 5.32, this will be a fatal error.
+string contains characters with values of 256 or higher, a fatal error
+will occur.
 
 Strings created with L<C<vec>|/vec EXPR,OFFSET,BITS> can also be
 manipulated with the logical