shell().exitcode is always 0 when :out is used

[p6rt]

Migrated from rt.perl.org#125757 (status was 'open')

Searchable as RT125757$

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From @hoelzro

See the attached script.

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From @hoelzro

test.pl

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From @hoelzro

On 2015-08-05 10​:32​:54, rob@​hoelz.ro wrote​:

See the attached script.

Same goes for run().

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From @ugexe

On Wed Aug 05 10​:32​:54 2015, rob@​hoelz.ro wrote​:

See the attached script.

It works if you close the file handle​:

perl6 -e 'my $p = shell("false", :out); $p.out.close; say $p.exitcode'
1

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From @FROGGS

Shall we attempt to make the exitcode (Int) until we got one?

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The RT System itself - Status changed from 'new' to 'open'

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From @hoelzro

On 2015-08-05 23​:20​:24, FROGGS.de wrote​:

Shall we attempt to make the exitcode (Int) until we got one?

That seems reasonable.

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From @AlexDaniel

First of all, let's look at the code that works​:
my $p = run 'bash', '-c', 'exit 5';
say $p.exitcode;

Result​:
5

Correct!

OK, now let's say I want to have the output as well​:
my $p = run 'bash', '-c', 'exit 5', :out;
say 'Out​: "' ~ $p.out.slurp-rest ~ '"';
say $p.exitcode;

Result​:
Out​: ""
0

But the exitcode is clearly not 0.

It turns out that you have to close .out in order to get it to work​:
my $p = run 'bash', '-c', 'exit 5', :out;
$p.out.close;
say $p.exitcode;

I think that it's fine if the exitcode is -1 until it is closed, yet I
don't understand why it does not close it automatically when I do
slurp-rest (perhaps it should?).

[p6rt]

From nxadm@apt-get.be

On Wed 05 Aug 2015 11​:21​:05, ugexe@​cpan.org wrote​:

On Wed Aug 05 10​:32​:54 2015, rob@​hoelz.ro wrote​:

See the attached script.

It works if you close the file handle​:

perl6 -e 'my $p = shell("false", :out); $p.out.close; say $p.exitcode'
1

There seem to be a regression​:
[claudio​:~/tmp] 1 $ perl6 -e 'my $p = shell("false", :out); $p.out.close; say $p.exitcode'
The spawned process exited unsuccessfully (exit code​: 1)
  in block <unit> at -e line 1

[claudio​:~/tmp] 1 $ perl6 -v
This is Rakudo version 2015.11-768-gfb475d2 built on MoarVM version 2015.11-113-gbd56e2e
implementing Perl 6.c.

This mean that real exit code when non-zero can not be retrieved. Adding a CATCH block can go around the chicken-and-egg problem​: exitcode can only be tested after close, but close throws an exception when exitcode is non-zero. However, this will no retrieve the real exitcode.

C.

[p6rt]

From @lucs

On Wed Jan 06 05​:56​:24 2016, nxadm wrote​:

On Wed 05 Aug 2015 11​:21​:05, ugexe@​cpan.org wrote​:

On Wed Aug 05 10​:32​:54 2015, rob@​hoelz.ro wrote​:

See the attached script.

It works if you close the file handle​:

perl6 -e 'my $p = shell("false", :out); $p.out.close; say
$p.exitcode'
1

There seem to be a regression​:
[claudio​:~/tmp] 1 $ perl6 -e 'my $p = shell("false", :out);
$p.out.close; say $p.exitcode'
The spawned process exited unsuccessfully (exit code​: 1)
in block <unit> at -e line 1

[claudio​:~/tmp] 1 $ perl6 -v
This is Rakudo version 2015.11-768-gfb475d2 built on MoarVM version
2015.11-113-gbd56e2e
implementing Perl 6.c.

This mean that real exit code when non-zero can not be retrieved.
Adding a CATCH block can go around the chicken-and-egg problem​:
exitcode can only be tested after close, but close throws an exception
when exitcode is non-zero. However, this will no retrieve the real
exitcode.

C.

Please note that assigning the result of the close() makes it work​:
$ perl6 -e 'my $p = shell("false", :out); my $x = $p.out.close; say $p.exitcode'
1

$ perl6 -v
This is Rakudo version 2015.12-218-gfb0a135 built on MoarVM version 2015.12-29-g8079ca5
implementing Perl 6.c.

[p6rt]

From @ugexe

The assignment fix can be simplified further​:
$ perl6 -e 'my $p = shell("false", :out); |$p.out.close; say $p.exitcode'
1

I would expect these 3 examples to have the same result. The actual results are `True, True, The spawned process exited unsuccessfully (exit code​: 1)`
`my $proc = run "perl6", "-e", "die", :out, :err; $proc.err.close; say ?$proc`
`my $proc = run "perl6", "-e", "die", :out, :err; $proc.err.close; $proc.out.close; say ?$proc`
`my $proc = run "perl6", "-e", "die", :out, :err; $proc.out.close; $proc.err.close; say ?$proc`

On Sun Jan 24 03​:15​:58 2016, scullucs wrote​:

On Wed Jan 06 05​:56​:24 2016, nxadm wrote​:

On Wed 05 Aug 2015 11​:21​:05, ugexe@​cpan.org wrote​:

On Wed Aug 05 10​:32​:54 2015, rob@​hoelz.ro wrote​:

See the attached script.

It works if you close the file handle​:

perl6 -e 'my $p = shell("false", :out); $p.out.close; say
$p.exitcode'
1

There seem to be a regression​:
[claudio​:~/tmp] 1 $ perl6 -e 'my $p = shell("false", :out);
$p.out.close; say $p.exitcode'
The spawned process exited unsuccessfully (exit code​: 1)
in block <unit> at -e line 1

[claudio​:~/tmp] 1 $ perl6 -v
This is Rakudo version 2015.11-768-gfb475d2 built on MoarVM version
2015.11-113-gbd56e2e
implementing Perl 6.c.

This mean that real exit code when non-zero can not be retrieved.
Adding a CATCH block can go around the chicken-and-egg problem​:
exitcode can only be tested after close, but close throws an
exception
when exitcode is non-zero. However, this will no retrieve the real
exitcode.

C.

Please note that assigning the result of the close() makes it work​:
$ perl6 -e 'my $p = shell("false", :out); my $x = $p.out.close; say
$p.exitcode'
1

$ perl6 -v
This is Rakudo version 2015.12-218-gfb0a135 built on MoarVM version
2015.12-29-g8079ca5
implementing Perl 6.c.

[p6rt]

From @briandfoy

It seems that the exit value that a Proc object returns isn't
always what I expect. In the calls where I specify :out, the
exit code seems to always be 0.

  use Test;

  my $program = '/usr/bin/false'; # maybe yours is different

  ok $program.IO.e, 'program exists';

  subtest {
  my $proc = run $program;
  is $proc.exitcode, 1, 'No arguments';
  }, 'run with no arguments';

  subtest {
  my $proc = run $program, :out;
  is $proc.exitcode, 1, 'Output specified, check exit before
read'; # is it finished running?
  $proc.out.slurp-rest;
  }, 'run with :out argument, read after';

  subtest {
  my $proc = run $program, :out;
  $proc.out.slurp-rest;
  is $proc.exitcode, 1, 'Output, check exit after read';
  }, 'run with :out argument, read first';

  subtest {
  my $null = $*SPEC.devnull.IO.open;
  # the program shouldn't compile and perl6 should return 1
  my $proc = run $*EXECUTABLE, '-c', $program, :out, :err($null);
  $proc.out.slurp-rest;
  is $proc.exitcode, 1, 'Output, check exit after read';
  }, 'compile check, read first';

  done-testing();

And, the output​:

  ok 1 - program exists
  ok 1 - No arguments
  1..1
  ok 2 - run with no arguments
  not ok 1 - Output specified, check exit before read
  1..1
  not ok 3 - run with :out argument, read after
  not ok 1 - Output, check exit after read
  1..1
  not ok 4 - run with :out argument, read first
  not ok 1 - Output, check exit after read
  1..1
  not ok 5 - run with :out argument, read first
  1..5

  # Failed test 'Output specified, check exit before read'
  # at /Users/brian/Desktop/false.p6 line 18
  # expected​: '1'
  # got​: '0'
  # Looks like you failed 1 test of 1

  # Failed test 'run with :out argument, read after'
  # at /Users/brian/Desktop/false.p6 line 16

  # Failed test 'Output, check exit after read'
  # at /Users/brian/Desktop/false.p6 line 25
  # expected​: '1'
  # got​: '0'
  # Looks like you failed 1 test of 1

  # Failed test 'run with :out argument, read first'
  # at /Users/brian/Desktop/false.p6 line 22

  # Failed test 'Output, check exit after read'
  # at /Users/brian/Desktop/false.p6 line 33
  # expected​: '1'
  # got​: '0'
  # Looks like you failed 1 test of 1

  # Failed test 'run with :out argument, read first'
  # at /Users/brian/Desktop/false.p6 line 28
  # Looks like you failed 3 tests of 5

The details​:

$ perl6 -v && uname -a
This is Rakudo version 2016.11 built on MoarVM version 2016.11
implementing Perl 6.c.
Darwin macpro.local 14.5.0 Darwin Kernel Version 14.5.0

[p6rt]

From @AlexDaniel

Dup of 125757

On 2017-01-26 18​:08​:59, comdog wrote​:

It seems that the exit value that a Proc object returns isn't
always what I expect. In the calls where I specify :out, the
exit code seems to always be 0.

use Test;

my $program = '/usr/bin/false'; # maybe yours is different

ok $program.IO.e, 'program exists';

subtest {
my $proc = run $program;
is $proc.exitcode, 1, 'No arguments';
}, 'run with no arguments';

subtest {
my $proc = run $program, :out;
is $proc.exitcode, 1, 'Output specified, check exit before
read'; # is it finished running?
$proc.out.slurp-rest;
}, 'run with :out argument, read after';

subtest {
my $proc = run $program, :out;
$proc.out.slurp-rest;
is $proc.exitcode, 1, 'Output, check exit after read';
}, 'run with :out argument, read first';

subtest {
my $null = $*SPEC.devnull.IO.open;
# the program shouldn't compile and perl6 should return 1
my $proc = run $*EXECUTABLE, '-c', $program, :out, :err($null);
$proc.out.slurp-rest;
is $proc.exitcode, 1, 'Output, check exit after read';
}, 'compile check, read first';

done-testing();

And, the output​:

ok 1 - program exists
ok 1 - No arguments
1..1
ok 2 - run with no arguments
not ok 1 - Output specified, check exit before read
1..1
not ok 3 - run with :out argument, read after
not ok 1 - Output, check exit after read
1..1
not ok 4 - run with :out argument, read first
not ok 1 - Output, check exit after read
1..1
not ok 5 - run with :out argument, read first
1..5

# Failed test 'Output specified, check exit before read'
# at /Users/brian/Desktop/false.p6 line 18
# expected​: '1'
# got​: '0'
# Looks like you failed 1 test of 1

# Failed test 'run with :out argument, read after'
# at /Users/brian/Desktop/false.p6 line 16

# Failed test 'Output, check exit after read'
# at /Users/brian/Desktop/false.p6 line 25
# expected​: '1'
# got​: '0'
# Looks like you failed 1 test of 1

# Failed test 'run with :out argument, read first'
# at /Users/brian/Desktop/false.p6 line 22

# Failed test 'Output, check exit after read'
# at /Users/brian/Desktop/false.p6 line 33
# expected​: '1'
# got​: '0'
# Looks like you failed 1 test of 1

# Failed test 'run with :out argument, read first'
# at /Users/brian/Desktop/false.p6 line 28
# Looks like you failed 3 tests of 5

The details​:

$ perl6 -v && uname -a
This is Rakudo version 2016.11 built on MoarVM version 2016.11
implementing Perl 6.c.
Darwin macpro.local 14.5.0 Darwin Kernel Version 14.5.0

[p6rt]

The RT System itself - Status changed from 'new' to 'open'

[p6rt]

From @timo

Hey Brian,

here's a version of your test code that works​:

  use Test;

  my $program = '/usr/bin/false'; # maybe yours is different

  ok $program.IO.e, 'program exists';

  subtest {
  my $proc = run $program;
  is $proc.exitcode, 1, 'No arguments';
  }, 'run with no arguments';

  subtest {
  my $proc = run $program, :out;
  $proc.out.slurp-rest(​:close);
  # is it finished running?
  is $proc.exitcode, 1, 'Output specified, check exit before read';
  }, 'run with :out argument, read after';

  subtest {
  my $proc = run $program, :out;
  $proc.out.slurp-rest(​:close);
  is $proc.exitcode, 1, 'Output, check exit after read';
  }, 'run with :out argument, read first';

  subtest {
  my $null = $*SPEC.devnull.IO.open;
  # the program shouldn't compile and perl6 should return 1
  my $proc = run $*EXECUTABLE, '-c', $program, :out, :err($null);
  $proc.out.slurp-rest(​:close);
  is $proc.exitcode, 1, 'Output, check exit after read';
  }, 'compile check, read first';

  done-testing();

Output​:

  ok 1 - program exists
  ok 1 - No arguments
  1..1
  ok 2 - run with no arguments
  ok 1 - Output specified, check exit before read
  1..1
  ok 3 - run with :out argument, read after
  ok 1 - Output, check exit after read
  1..1
  ok 4 - run with :out argument, read first
  ok 1 - Output, check exit after read
  1..1
  ok 5 - compile check, read first
  1..5

you need to pass :close to slurp-rest so that it closes the output pipe, otherwise your program will keep running and won't actually exit.

Please note that i also re-ordered things in the second subtest.

There's been discussion that running .exitcode either while the program is still running or while out/err aren't closed should throw an exception immediately.