=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</[[:isalnum:]]/> construct instead, or possibly the C</\w/> construct.
+C</[[:alnum:]]/> construct instead, or possibly the C</\w/> construct.
=item isalpha
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</[[:isalpha:]]/> construct instead.
+C</[[:alpha:]]/> construct instead.
=item isatty
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</[[:iscntrl:]]/> construct instead.
+C</[[:cntrl:]]/> construct instead.
=item isdigit
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</[[:isdigit:]]/> construct instead, or the C</\d/> construct.
+C</[[:digit:]]/> construct instead, or the C</\d/> construct.
=item isgraph
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</[[:isgraph:]]/> construct instead.
+C</[[:graph:]]/> construct instead.
=item islower
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</[[:islower:]]/> 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</[[:isprint:]]/> construct instead.
+C</[[:print:]]/> construct instead.
=item ispunct
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</[[:ispunct:]]/> construct instead.
+C</[[:punct:]]/> construct instead.
=item isspace
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</[[:isspace:]]/> construct instead, or the C</\s/> construct.
+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</[[:isupper:]]/> construct instead. Do B<not> use C</A-Z/>.
+C</[[:upper:]]/> construct instead. Do B<not> use C</[A-Z]/>.
=item isxdigit
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</[[:isxdigit:]]/> construct instead, or simply C</[0-9a-f]/i>.
+C</[[:xdigit:]]/> construct instead, or simply C</[0-9a-f]/i>.
=item kill
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, "" );
$tmpfile = POSIX::tmpnam();
-See also L<File::Temp>.
+For security reasons, which are probably detailed in your system's
+documentation for the C library tmpnam() function, this interface
+should not be used; instead see L<File::Temp>.
=item tolower
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