=item clearerr
-Use the method L<IO::Handle::clearerr()> instead, to reset the error
+Use the method C<IO::Handle::clearerr()> instead, to reset the error
state (if any) and EOF state (if any) of the given stream.
=item clock
This is identical to the C function, except that it can apply to a single
character or to a whole string. Consider using regular expressions and the
-C</[[:lower:]]/> construct instead. Do B<not> use C</a-z/>.
+C</[[:lower:]]/> construct instead. Do B<not> use C</[a-z]/>.
=item isprint
This is identical to the C function, except that it can apply to a single
character or to a whole string. Consider using regular expressions and the
C</[[:space:]]/> construct instead, or the C</\s/> construct.
+(Note that C</\s/> and C</[[:space:]]/> are slightly different in that
+C</[[:space:]]/> can normally match a vertical tab, while C</\s/> does
+not.)
=item isupper
This is identical to the C function, except that it can apply to a single
character or to a whole string. Consider using regular expressions and the
-C</[[:upper:]]/> construct instead. Do B<not> use C</A-Z/>.
+C</[[:upper:]]/> construct instead. Do B<not> use C</[A-Z]/>.
=item isxdigit
The following will set the LC_CTYPE behaviour according to the locale
environment variables (the second argument C<"">).
-Please see your systems L<setlocale(3)> documentation for the locale
+Please see your systems C<setlocale(3)> documentation for the locale
environment variables' meaning or consult L<perllocale>.
$loc = setlocale( LC_CTYPE, "" );
$str = POSIX::strftime( "%A, %B %d, %Y", 0, 0, 0, 12, 11, 95, 2 );
print "$str\n";
-See also L<Time::Piece>.
-
=item strlen
strlen() is C-specific, use C<length()> instead, see L<perlfunc/length>.
Wait for a child process to change state. This is identical to Perl's
builtin C<waitpid()> function, see L<perlfunc/waitpid>.
- $pid = POSIX::waitpid( -1, &POSIX::WNOHANG );
+ $pid = POSIX::waitpid( -1, POSIX::WNOHANG );
print "status = ", ($? / 256), "\n";
=item wcstombs
WNOHANG WUNTRACED
+=over 16
+
+=item WNOHANG
+
+Do not suspend the calling process until a child process
+changes state but instead return immediately.
+
+=item WUNTRACED
+
+Catch stopped child processes.
+
+=back
+
=item Macros
WIFEXITED WEXITSTATUS WIFSIGNALED WTERMSIG WIFSTOPPED WSTOPSIG
+=over 16
+
+=item WIFEXITED
+
+WIFEXITED($?) returns true if the child process exited normally
+(C<exit()> or by falling off the end of C<main()>)
+
+=item WEXITSTATUS
+
+WEXITSTATUS($?) returns the normal exit status of the child process
+(only meaningful if WIFEXITED($?) is true)
+
+=item WIFSIGNALED
+
+WIFSIGNALED($?) returns true if the child process terminated because
+of a signal
+
+=item WTERMSIG
+
+WTERMSIG($?) returns the signal the child process terminated for
+(only meaningful if WIFSIGNALED($?) is true)
+
+=item WIFSTOPPED
+
+WIFSTOPPED($?) returns true if the child process is currently stopped
+(can happen only if you specified the WUNTRACED flag to waitpid())
+
+=item WSTOPSIG
+
+WSTOPSIG($?) returns the signal the child process was stopped for
+(only meaningful if WIFSTOPPED($?) is true)
+
+=back
+
=back