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#!./perl
BEGIN {
chdir 't' if -d 't';
require './test.pl';
set_up_inc('../lib');
}
plan tests => 45;
open(I, 'op/sysio.t') || die "sysio.t: cannot find myself: $!";
binmode I;
$reopen = ($^O eq 'VMS' ||
$^O eq 'os2' ||
$^O eq 'MSWin32');
$x = 'abc';
# should not be able to do negative lengths
eval { sysread(I, $x, -1) };
like($@, qr/^Negative length /);
# $x should be intact
is($x, 'abc');
# should not be able to read before the buffer
eval { sysread(I, $x, 1, -4) };
like($@, qr/^Offset outside string /);
# $x should be intact
is($x, 'abc');
$a ='0123456789';
# default offset 0
is(sysread(I, $a, 3), 3);
# $a should be as follows
is($a, '#!.');
# reading past the buffer should zero pad
is(sysread(I, $a, 2, 5), 2);
# the zero pad should be seen now
is($a, "#!.\0\0/p");
# try changing the last two characters of $a
is(sysread(I, $a, 3, -2), 3);
# the last two characters of $a should have changed (into three)
is($a, "#!.\0\0erl");
$outfile = tempfile();
open(O, ">$outfile") || die "sysio.t: cannot write $outfile: $!";
binmode O;
select(O); $|=1; select(STDOUT);
# cannot write negative lengths
eval { syswrite(O, $x, -1) };
like($@, qr/^Negative length /);
# $x still intact
is($x, 'abc');
# $outfile still intact
ok(!-s $outfile);
# should not be able to write from after the buffer
eval { syswrite(O, $x, 1, 4) };
like($@, qr/^Offset outside string /);
# $x still intact
is($x, 'abc');
# but it should be ok to write from the end of the buffer
syswrite(O, $x, 0, 3);
syswrite(O, $x, 1, 3);
# $outfile still intact
if ($reopen) { # must close file to update EOF marker for stat
close O; open(O, ">>$outfile") || die "sysio.t: cannot write $outfile: $!";
binmode O;
}
ok(!-s $outfile);
# should not be able to write from before the buffer
eval { syswrite(O, $x, 1, -4) };
like($@, qr/^Offset outside string /);
# $x still intact
is($x, 'abc');
# $outfile still intact
if ($reopen) { # must close file to update EOF marker for stat
close O; open(O, ">>$outfile") || die "sysio.t: cannot write $outfile: $!";
binmode O;
}
ok(!-s $outfile);
# [perl #67912] syswrite prints garbage if called with empty scalar and non-zero offset
eval { my $buf = ''; syswrite(O, $buf, 1, 1) };
like($@, qr/^Offset outside string /);
# $x still intact
is($x, 'abc');
# $outfile still intact
if ($reopen) { # must close file to update EOF marker for stat
close O; open(O, ">>$outfile") || die "sysio.t: cannot write $outfile: $!";
binmode O;
}
ok(!-s $outfile);
eval { my $buf = 'x'; syswrite(O, $buf, 1, 2) };
like($@, qr/^Offset outside string /);
# $x still intact
is($x, 'abc');
# $outfile still intact
if ($reopen) { # must close file to update EOF marker for stat
close O; open(O, ">>$outfile") || die "sysio.t: cannot write $outfile: $!";
binmode O;
}
ok(!-s $outfile);
# default offset 0
if (syswrite(O, $a, 2) == 2){
pass();
} else {
diag($!);
fail();
# most other tests make no sense after e.g. "No space left on device"
die $!;
}
# $a still intact
is($a, "#!.\0\0erl");
# $outfile should have grown now
if ($reopen) { # must close file to update EOF marker for stat
close O; open(O, ">>$outfile") || die "sysio.t: cannot write $outfile: $!";
binmode O;
}
is(-s $outfile, 2);
# with offset
is(syswrite(O, $a, 2, 5), 2);
# $a still intact
is($a, "#!.\0\0erl");
# $outfile should have grown now
if ($reopen) { # must close file to update EOF marker for stat
close O; open(O, ">>$outfile") || die "sysio.t: cannot write $outfile: $!";
binmode O;
}
is(-s $outfile, 4);
# with negative offset and a bit too much length
is(syswrite(O, $a, 5, -3), 3);
# $a still intact
is($a, "#!.\0\0erl");
# $outfile should have grown now
if ($reopen) { # must close file to update EOF marker for stat
close O; open(O, ">>$outfile") || die "sysio.t: cannot write $outfile: $!";
binmode O;
}
is(-s $outfile, 7);
# with implicit length argument
is(syswrite(O, $x), 3);
# $a still intact
is($x, "abc");
# $outfile should have grown now
if ($reopen) { # must close file to update EOF marker for stat
close O; open(O, ">>$outfile") || die "sysio.t: cannot write $outfile: $!";
binmode O;
}
is(-s $outfile, 10);
close(O);
open(I, $outfile) || die "sysio.t: cannot read $outfile: $!";
binmode I;
$b = 'xyz';
# reading too much only return as much as available
is(sysread(I, $b, 100), 10);
# this we should have
is($b, '#!ererlabc');
# test sysseek
is(sysseek(I, 2, 0), 2);
sysread(I, $b, 3);
is($b, 'ere');
is(sysseek(I, -2, 1), 3);
sysread(I, $b, 4);
is($b, 'rerl');
ok(sysseek(I, 0, 0) eq '0 but true');
ok(not defined sysseek(I, -1, 1));
close(I);
unlink_all $outfile;
chdir('..');
1;
# eof