Skip test for changing TZ if running in a pseudo-fork (on Win32)

[p5sagit/p5-mst-13.2.git] / pod / perlport.pod

diff --git a/pod/perlport.pod b/pod/perlport.pod
index e7a8ca5..9920a83 100644 (file)
--- a/pod/perlport.pod
+++ b/pod/perlport.pod
@@ -433,6 +433,16 @@ if you really have to, make it conditional on C<$^O ne 'VMS'> since in
 VMS the C<%ENV> table is much more than a per-process key-value string
 table.
 
+On VMS, some entries in the %ENV hash are dynamically created when
+their key is used on a read if they did not previously exist.  The
+values for C<$ENV{HOME}>, C<$ENV{TERM}>, C<$ENV{HOME}>, and C<$ENV{USER}>,
+are known to be dynamically generated.  The specific names that are
+dynamically generated may vary with the version of the C library on VMS,
+and more may exist than is documented.
+
+On VMS by default, changes to the %ENV hash are persistent after the process
+exits.  This can cause unintended issues.
+
 Don't count on signals or C<%SIG> for anything.
 
 Don't count on filename globbing.  Use C<opendir>, C<readdir>, and
@@ -631,9 +641,6 @@ The value for C<$offset> in Unix will be C<0>, but in Mac OS will be
 some large number.  C<$offset> can then be added to a Unix time value
 to get what should be the proper value on any system.
 
-On Windows (at least), you shouldn't pass a negative value to C<gmtime> or
-C<localtime>.
-
 =head2 Character sets and character encoding
 
 Assume very little about character sets.
@@ -805,6 +812,7 @@ are a few of the more popular Unix flavors:
     dgux          dgux       AViiON-dgux
     DYNIX/ptx     dynixptx   i386-dynixptx
     FreeBSD       freebsd    freebsd-i386    
+    Haiku         haiku      BePC-haiku
     Linux         linux      arm-linux
     Linux         linux      i386-linux
     Linux         linux      i586-linux
@@ -1249,7 +1257,8 @@ names, because the VOS port of Perl interprets it as a pathname
 delimiting character, VOS files, directories, or links whose names
 contain a slash character cannot be processed.  Such files must be
 renamed before they can be processed by Perl.  Note that VOS limits
-file names to 32 or fewer characters.
+file names to 32 or fewer characters, file names cannot start with a
+C<-> character, or contain any character matching C<< tr/ !%&'()*+;<>?// >>
 
 The value of C<$^O> on VOS is "VOS".  To determine the architecture that
 you are running on without resorting to loading all of C<%Config> you
@@ -1570,6 +1579,11 @@ C<-r>, C<-w>, and C<-x> have a limited meaning only; directories
 and applications are executable, and there are no uid/gid
 considerations.  C<-o> is not supported.  (S<Mac OS>)
 
+C<-w> only inspects the read-only file attribute (FILE_ATTRIBUTE_READONLY),
+which determines whether the directory can be deleted, not whether it can
+be written to. Directories always have read and write access unless denied
+by discretionary access control lists (DACLs).  (S<Win32>)
+
 C<-r>, C<-w>, C<-x>, and C<-o> tell whether the file is accessible,
 which may not reflect UIC-based file protections.  (VMS)
 
@@ -1586,9 +1600,11 @@ C<-x>, C<-o>. (S<Mac OS>, Win32, VMS, S<RISC OS>)
 C<-b>, C<-c>, C<-k>, C<-g>, C<-p>, C<-u>, C<-A> are not implemented.
 (S<Mac OS>)
 
-C<-g>, C<-k>, C<-l>, C<-p>, C<-u>, C<-A> are not particularly meaningful.
+C<-g>, C<-k>, C<-l>, C<-u>, C<-A> are not particularly meaningful.
 (Win32, VMS, S<RISC OS>)
 
+C<-p> is not particularly meaningful. (VMS, S<RISC OS>)
+
 C<-d> is true if passed a device spec without an explicit directory.
 (VMS)
 
@@ -1847,7 +1863,10 @@ platforms.  See L<File::Glob> for portability information.
 
 =item gmtime
 
-Same portability caveats as L<localtime>.
+In theory, gmtime() is reliable from -2**63 to 2**63-1.  However,
+because work arounds in the implementation use floating point numbers,
+it will become inaccurate as the time gets larger.  This is a bug and
+will be fixed in the future.
 
 =item ioctl FILEHANDLE,FUNCTION,SCALAR
 
@@ -1872,6 +1891,12 @@ and makes it exit immediately with exit status $sig.  As in Unix, if
 $sig is 0 and the specified process exists, it returns true without
 actually terminating it. (Win32)
 
+C<kill(-9, $pid)> will terminate the process specified by $pid and
+recursively all child processes owned by it.  This is different from
+the Unix semantics, where the signal will be delivered to all
+processes in the same process group as the process specified by
+$pid. (Win32)
+
 Is not supported for process identification number of 0 or negative
 numbers. (VMS)
 
@@ -1892,10 +1917,9 @@ Available on 64 bit OpenVMS 8.2 and later.  (VMS)
 
 =item localtime
 
-Because Perl currently relies on the native standard C localtime()
-function, it is only safe to use times between 0 and (2**31)-1.  Times
-outside this range may result in unexpected behavior depending on your
-operating system's implementation of localtime().
+localtime() has the same range as L<gmtime>, but because time zone
+rules change its accuracy for historical and future times may degrade
+but usually by no more than an hour.
 
 =item lstat
 
@@ -1988,7 +2012,7 @@ be implemented even in UNIX platforms.
 
 =item socketpair
 
-Not implemented. (Win32, S<RISC OS>, VOS, VM/ESA)
+Not implemented. (S<RISC OS>, VOS, VM/ESA)
 
 Available on 64 bit OpenVMS 8.2 and later.  (VMS)
 
@@ -2025,7 +2049,10 @@ not performing this operation. (Win32)
 
 =item symlink
 
-Not implemented. (Win32, VMS, S<RISC OS>)
+Not implemented. (Win32, S<RISC OS>)
+
+Implemented on 64 bit VMS 8.3.  VMS requires the symbolic link to be in Unix
+syntax if it is intended to resolve to a valid path.
 
 =item syscall