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Groups > comp.lang.java.programmer > #23618

Re: exec problem is JDK 1.7.0_21

From Steven Simpson <ss@domain.invalid>
Newsgroups comp.lang.java.programmer
Subject Re: exec problem is JDK 1.7.0_21
Date 2013-04-24 10:26 +0100
Organization A noiseless patient Spider
Message-ID <c2lk4a-od3.ln1@s.simpson148.btinternet.com> (permalink)
References (7 earlier) <e02i4a-8m3.ln1@s.simpson148.btinternet.com> <k32j4a-gk4.ln1@s.simpson148.btinternet.com> <ato9c2FmrfdU2@mid.dfncis.de> <r5fj4a-jd7.ln1@s.simpson148.btinternet.com> <atpce0FtpndU1@mid.dfncis.de>

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On 24/04/13 07:29, Sven Köhler wrote:
> Am 24.04.2013 01:39, schrieb Steven Simpson:
>>> Also, you have to add another backslash if the quote does not terminate
>>> the argument.
>> Again, I took it to mean that the first two rules produce the same
>> result, so \\\" and \\" both produce \".
> The documentation of CommandLineToArgv is incomplete.

Agreed.

>> Where are you getting the notion that the first two rules imply
>> different quotes?  I interpret both as being literal (inner, right?).
> Well, by testing. As you can test yourself on the command line, \\" will
> result in a closing quote and \" and \\\" will result in non-closing quotes.

That's not what I'm seeing.  In fact, backslashes appear to have no effect!

Cross-compiled with mingw32:

#include <windows.h>
#include <shellapi.h>

#include <stdio.h>
#include <wchar.h>

static void test(const wchar_t *s)
{
   printf("\nInput line: %ls\n", s);
   int argc;
   LPWSTR *argv = CommandLineToArgvW(s, &argc);
   if (!argv) {
     printf("  unable to parse\n");
   } else {
     printf("  arg count: %d\n", argc);
     for (int i = 0; i < argc; i++)
       printf("  [%d]=[%ls]\n", i, argv[i]);
     LocalFree(argv);
   }
}

int main(void)
{
   test(L"foo");
   test(L"foo\"");
   test(L"foo\\\"");
   test(L"foo\\\\\"");
   test(L"foo\\\\\\\"");

   test(L"\"foo");
   test(L"\"foo\"");
   test(L"\"foo\\\"");
   test(L"\"foo\\\\\"");
   test(L"\"foo\\\\\\\"");

   test(L"foo bar");
   test(L"foo\"bar");
   test(L"foo\\\"bar");
   test(L"foo\\\\\"bar");
   test(L"foo\\\\\\\"bar");
  
   test(L"foo\\ bar");
   test(L"foo\\\\ bar");
   test(L"foo\\\\\\ bar");

   test(L"\"foo bar\"");
   test(L"\"foo \\\"bar\"");
   test(L"\"foo \\\\\"bar\"");
   test(L"\"foo \\\\\\\"bar\"");

   return 0;
}




Output:

Input line: foo
   arg count: 1
   [0]=[foo]

Input line: foo"
   arg count: 1
   [0]=[foo"]

Okay, so if the quote doesn't start the argument, it's literal.


Input line: foo\"
   arg count: 1
   [0]=[foo\"]

Input line: foo\\"
   arg count: 1
   [0]=[foo\\"]

Input line: foo\\\"
   arg count: 1
   [0]=[foo\\\"]

These backslashes aren't folded in any way.

Input line: "foo
   arg count: 1
   [0]=[foo]

Input line: "foo"
   arg count: 1
   [0]=[foo]

So the leading quote is stripped, and the closing quote is optional - no 
error.


Input line: "foo\"
   arg count: 1
   [0]=[foo\]

Input line: "foo\\"
   arg count: 1
   [0]=[foo\\]

Input line: "foo\\\"
   arg count: 1
   [0]=[foo\\\]

Inside the quoted argument, backslashes still have no special meaning.  
And I can't get a literal quote character.


Input line: foo bar
   arg count: 2
   [0]=[foo]
   [1]=[bar]

So a space splits arguments.


Input line: foo"bar
   arg count: 1
   [0]=[foo"bar]

The quote inside an unquoted argument is taken as literal.


Input line: foo\"bar
   arg count: 1
   [0]=[foo\"bar]

Input line: foo\\"bar
   arg count: 1
   [0]=[foo\\"bar]

Input line: foo\\\"bar
   arg count: 1
   [0]=[foo\\\"bar]

The backslashes are literal in the middle of the unquoted argument.


Input line: foo\ bar
   arg count: 2
   [0]=[foo\]
   [1]=[bar]

Input line: foo\\ bar
   arg count: 2
   [0]=[foo\\]
   [1]=[bar]

Input line: foo\\\ bar
   arg count: 2
   [0]=[foo\\\]
   [1]=[bar]

Just checking that there's no unspecified way to escape a space.


Input line: "foo bar"
   arg count: 1
   [0]=[foo bar]

The quotes cause the space to be taken literally.


Input line: "foo \"bar"
   arg count: 2
   [0]=[foo \]
   [1]=[bar]

Input line: "foo \\"bar"
   arg count: 2
   [0]=[foo \\]
   [1]=[bar]

Input line: "foo \\\"bar"
   arg count: 2
   [0]=[foo \\\]
   [1]=[bar]

Backslashes are still literal, and the next quote closes the argument 
regardless.  Plus, the extra quote after [bar] is not literal.

There seems to be no way to escape a space other than enclosing the 
entire argument in quotes.  Once inside the quotes, there's no way to 
escape anything else (like a literal quote), so there's no way to escape 
an argument containing a space and a quote.  Backslashes behave 
literally everywhere.

Is the program using CommandLineToArgvW incorrectly?  Are there any 
other input strings to try?



> Also, there HAS to be a way to distinguish a closing vs. a non-closing
> quote. Otherwise you wouldn't know whether the quotes in \" \\" and \\\"
> were closing or not. That's it is not documented is just a real shame!

What I'm seeing now is that general escaping is impossible, not merely 
documented badly.  :-(


-- 
ss at comp dot lancs dot ac dot uk

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Thread

exec problem is JDK 1.7.0_21 Roedy Green <see_website@mindprod.com.invalid> - 2013-04-16 15:48 -0700
  Re: exec problem is JDK 1.7.0_21 Lew <lewbloch@gmail.com> - 2013-04-16 16:48 -0700
  Re: exec problem is JDK 1.7.0_21 Sven Köhler <remove-sven.koehler@gmail.com> - 2013-04-20 13:00 +0300
  Re: exec problem is JDK 1.7.0_21 Joerg Meier <joergmmeier@arcor.de> - 2013-04-20 15:13 +0200
    Re: exec problem is JDK 1.7.0_21 Sven Köhler <remove-sven.koehler@gmail.com> - 2013-04-20 19:07 +0300
      Re: exec problem is JDK 1.7.0_21 markspace <markspace@nospam.nospam> - 2013-04-20 09:24 -0700
        Re: exec problem is JDK 1.7.0_21 Sven Köhler <remove-sven.koehler@gmail.com> - 2013-04-20 19:34 +0300
          Re: exec problem is JDK 1.7.0_21 markspace <markspace@nospam.nospam> - 2013-04-20 11:01 -0700
            Re: exec problem is JDK 1.7.0_21 Sven Köhler <remove-sven.koehler@gmail.com> - 2013-04-21 00:25 +0300
          Re: exec problem is JDK 1.7.0_21 Joerg Meier <joergmmeier@arcor.de> - 2013-04-20 22:03 +0200
            Re: exec problem is JDK 1.7.0_21 Sven Köhler <remove-sven.koehler@gmail.com> - 2013-04-21 00:29 +0300
              Re: exec problem is JDK 1.7.0_21 Martin Gregorie <martin@address-in-sig.invalid> - 2013-04-20 21:56 +0000
                Re: exec problem is JDK 1.7.0_21 Sven Köhler <remove-sven.koehler@gmail.com> - 2013-04-21 08:31 +0300
                Re: exec problem is JDK 1.7.0_21 Martin Gregorie <martin@address-in-sig.invalid> - 2013-04-21 11:08 +0000
                Re: exec problem is JDK 1.7.0_21 Arved Sandstrom <asandstrom2@eastlink.ca> - 2013-04-21 13:43 -0300
                Re: exec problem is JDK 1.7.0_21 Sven Köhler <remove-sven.koehler@gmail.com> - 2013-04-21 23:12 +0300
                Re: exec problem is JDK 1.7.0_21 Martin Gregorie <martin@address-in-sig.invalid> - 2013-04-21 21:17 +0000
                Re: exec problem is JDK 1.7.0_21 Arne Vajhøj <arne@vajhoej.dk> - 2013-04-27 22:49 -0400
              Re: exec problem is JDK 1.7.0_21 Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2013-04-20 15:03 -0700
                Re: exec problem is JDK 1.7.0_21 Sven Köhler <remove-sven.koehler@gmail.com> - 2013-04-21 08:26 +0300
                Re: exec problem is JDK 1.7.0_21 "Chris Uppal" <chris.uppal@metagnostic.REMOVE-THIS.org> - 2013-04-21 14:30 +0100
                Re: exec problem is JDK 1.7.0_21 Knute Johnson <nospam@knutejohnson.com> - 2013-04-21 09:20 -0700
                Re: exec problem is JDK 1.7.0_21 markspace <markspace@nospam.nospam> - 2013-04-21 11:31 -0700
                Re: exec problem is JDK 1.7.0_21 Arved Sandstrom <asandstrom2@eastlink.ca> - 2013-04-21 16:06 -0300
                Re: exec problem is JDK 1.7.0_21 Martin Gregorie <martin@address-in-sig.invalid> - 2013-04-21 19:47 +0000
                Re: exec problem is JDK 1.7.0_21 Martin Gregorie <martin@address-in-sig.invalid> - 2013-04-21 23:01 +0000
                Re: exec problem is JDK 1.7.0_21 Sven Köhler <remove-sven.koehler@gmail.com> - 2013-04-21 23:29 +0300
                Re: exec problem is JDK 1.7.0_21 Sven Köhler <remove-sven.koehler@gmail.com> - 2013-04-21 23:45 +0300
                Re: exec problem is JDK 1.7.0_21 Martin Gregorie <martin@address-in-sig.invalid> - 2013-04-21 21:38 +0000
                Re: exec problem is JDK 1.7.0_21 Knute Johnson <nospam@knutejohnson.com> - 2013-04-21 18:49 -0700
                Re: exec problem is JDK 1.7.0_21 Sven Köhler <remove-sven.koehler@gmail.com> - 2013-04-22 09:36 +0300
                Re: exec problem is JDK 1.7.0_21 Steven Simpson <ss@domain.invalid> - 2013-04-22 10:39 +0100
                Re: exec problem is JDK 1.7.0_21 Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2013-04-22 07:43 -0700
                Re: exec problem is JDK 1.7.0_21 Sven Köhler <remove-sven.koehler@gmail.com> - 2013-04-22 19:33 +0300
                Re: exec problem is JDK 1.7.0_21 Steven Simpson <ss@domain.invalid> - 2013-04-23 07:30 +0100
                Re: exec problem is JDK 1.7.0_21 Martin Gregorie <martin@address-in-sig.invalid> - 2013-04-22 21:07 +0000
                Re: exec problem is JDK 1.7.0_21 Sven Köhler <remove-sven.koehler@gmail.com> - 2013-04-23 23:28 +0300
                Re: exec problem is JDK 1.7.0_21 Martin Gregorie <martin@address-in-sig.invalid> - 2013-04-23 21:05 +0000
                Re: exec problem is JDK 1.7.0_21 Sven Köhler <remove-sven.koehler@gmail.com> - 2013-04-24 11:22 +0300
                Re: exec problem is JDK 1.7.0_21 Martin Gregorie <martin@address-in-sig.invalid> - 2013-04-24 20:22 +0000
                Re: exec problem is JDK 1.7.0_21 Nigel Wade <nmw@ion.le.ac.uk> - 2013-04-24 11:24 +0100
                Re: exec problem is JDK 1.7.0_21 Sven Köhler <remove-sven.koehler@gmail.com> - 2013-04-21 23:23 +0300
            Re: exec problem is JDK 1.7.0_21 Sven Köhler <remove-sven.koehler@gmail.com> - 2013-04-21 00:40 +0300
              Re: exec problem is JDK 1.7.0_21 Steven Simpson <ss@domain.invalid> - 2013-04-23 10:48 +0100
                Re: exec problem is JDK 1.7.0_21 Donkey Hottie <donkey@fredriksson.dy.fi> - 2013-04-23 13:31 +0300
                <? extends String> (was: exec problem is JDK 1.7.0_21) Steven Simpson <ss@domain.invalid> - 2013-04-23 14:55 +0100
                Re: <? extends String> lipska the kat <"nospam at neversurrender dot co dot uk"> - 2013-04-23 16:37 +0100
                Re: <? extends String> Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2013-04-23 08:50 -0700
                Re: <? extends String> lipska the kat <"nospam at neversurrender dot co dot uk"> - 2013-04-23 17:30 +0100
                Re: <? extends String> Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2013-04-23 09:58 -0700
                Re: <? extends String> Donkey Hottie <donkey@fredriksson.dy.fi> - 2013-04-23 21:06 +0300
                Re: <? extends String> lipska the kat <"nospam at neversurrender dot co dot uk"> - 2013-04-23 19:33 +0100
                Re: <? extends String> Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2013-04-23 12:26 -0700
                Re: <? extends String> lipska the kat <"nospam at neversurrender dot co dot uk"> - 2013-04-24 09:08 +0100
                Re: <? extends String> Arved Sandstrom <asandstrom2@eastlink.ca> - 2013-04-23 16:28 -0300
                Re: <? extends String> (was: exec problem is JDK 1.7.0_21) Lew <lewbloch@gmail.com> - 2013-04-23 14:12 -0700
                Re: <? extends String> Steven Simpson <ss@domain.invalid> - 2013-04-23 23:22 +0100
                Re: exec problem is JDK 1.7.0_21 Steven Simpson <ss@domain.invalid> - 2013-04-23 19:56 +0100
                Re: exec problem is JDK 1.7.0_21 Sven Köhler <remove-sven.koehler@gmail.com> - 2013-04-23 23:31 +0300
                Re: exec problem is JDK 1.7.0_21 Steven Simpson <ss@domain.invalid> - 2013-04-23 23:39 +0100
                Re: exec problem is JDK 1.7.0_21 Sven Köhler <remove-sven.koehler@gmail.com> - 2013-04-24 09:29 +0300
                Re: exec problem is JDK 1.7.0_21 Steven Simpson <ss@domain.invalid> - 2013-04-24 10:26 +0100
                Re: exec problem is JDK 1.7.0_21 Sven Köhler <remove-sven.koehler@gmail.com> - 2013-04-24 13:11 +0300
                Re: exec problem is JDK 1.7.0_21 Steven Simpson <ss@domain.invalid> - 2013-04-24 22:24 +0100
                Re: exec problem is JDK 1.7.0_21 Sven Köhler <remove-sven.koehler@gmail.com> - 2013-04-25 11:49 +0300
                Re: exec problem is JDK 1.7.0_21 Steven Simpson <ss@domain.invalid> - 2013-04-25 10:19 +0100
                Re: exec problem is JDK 1.7.0_21 "Chris Uppal" <chris.uppal@metagnostic.REMOVE-THIS.org> - 2013-04-25 09:02 +0100
                Re: exec problem is JDK 1.7.0_21 Sven Köhler <remove-sven.koehler@gmail.com> - 2013-04-25 11:47 +0300
                Re: exec problem is JDK 1.7.0_21 Steven Simpson <ss@domain.invalid> - 2013-04-25 09:50 +0100
                Re: exec problem is JDK 1.7.0_21 Steven Simpson <ss@domain.invalid> - 2013-04-25 10:07 +0100
                Re: exec problem is JDK 1.7.0_21 "Chris Uppal" <chris.uppal@metagnostic.REMOVE-THIS.org> - 2013-04-27 08:44 +0100
                Re: exec problem is JDK 1.7.0_21 Sven Köhler <remove-sven.koehler@gmail.com> - 2013-04-26 20:17 +0300
                Re: exec problem is JDK 1.7.0_21 Steven Simpson <ss@domain.invalid> - 2013-04-27 09:22 +0100
                Re: exec problem is JDK 1.7.0_21 Sven Köhler <remove-sven.koehler@gmail.com> - 2013-04-27 12:39 +0300
                Re: exec problem is JDK 1.7.0_21 Sven Köhler <remove-sven.koehler@gmail.com> - 2013-04-23 23:17 +0300
                Re: exec problem is JDK 1.7.0_21 Arved Sandstrom <asandstrom2@eastlink.ca> - 2013-04-23 17:32 -0300
                Re: exec problem is JDK 1.7.0_21 Sven Köhler <remove-sven.koehler@gmail.com> - 2013-04-24 10:39 +0300
                Re: exec problem is JDK 1.7.0_21 "Chris Uppal" <chris.uppal@metagnostic.REMOVE-THIS.org> - 2013-04-25 09:02 +0100
                Re: exec problem is JDK 1.7.0_21 Sven Köhler <remove-sven.koehler@gmail.com> - 2013-04-25 11:59 +0300
                Re: exec problem is JDK 1.7.0_21 Arved Sandstrom <asandstrom2@eastlink.ca> - 2013-04-25 18:38 -0300
                Re: exec problem is JDK 1.7.0_21 Sven Köhler <remove-sven.koehler@gmail.com> - 2013-04-28 10:57 +0300
                Re: exec problem is JDK 1.7.0_21 Arne Vajhøj <arne@vajhoej.dk> - 2013-04-27 22:35 -0400
                Re: exec problem is JDK 1.7.0_21 Sven Köhler <remove-sven.koehler@gmail.com> - 2013-04-28 09:23 +0300
                Re: exec problem is JDK 1.7.0_21 Arne Vajhøj <arne@vajhoej.dk> - 2013-04-28 09:52 -0400
  Re: exec problem is JDK 1.7.0_21 Stanimir Stamenkov <s7an10@netscape.net> - 2013-04-20 17:52 +0300
    Re: exec problem is JDK 1.7.0_21 Arne Vajhøj <arne@vajhoej.dk> - 2013-04-27 22:31 -0400

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