no warnings 'io' ;
my $a = sysread(F, $a,10) ;
close F ;
+use warnings 'io' ;
+sysread(F, $a, 10);
+read(F, $a, 10);
+sysread(NONEXISTENT, $a, 10);
+read(NONEXISTENT, $a, 10);
unlink $file ;
EXPECT
Filehandle F opened only for output at - line 12.
+sysread() on closed filehandle F at - line 17.
+read() on closed filehandle F at - line 18.
+sysread() on unopened filehandle NONEXISTENT at - line 19.
+read() on unopened filehandle NONEXISTENT at - line 20.
########
# pp_sys.c [pp_binmode]
use warnings 'unopened' ;