Question

如何在Windows 上使用std :: system运行带空格的可执行文件而不使用C ++ 11 ？

我已尝试用空格在路径周围放置看似明显的引号，但在弹出运行命令的控制台窗口中，我收到一条消息，指示完整的可执行路径正在空格中分割。例如，我尝试过以下方法：

#include <cstdlib>

int main()
{
    int no_spaces_forward_rc = std::system("c:/IronPython2.7/ipy -c \"print 'no_spaces_forward'\"");
    // no_spaces_forward_rc is 0 and "no_spaces_forward" is written to console window

    int spaces_forward_rc    = std::system("\"c:/Program Files (x86)/IronPython 2.7/ipy\" -c \"print 'spaces_forward'\"");
    // spaces_forward_rc is 1, and "'c:/Program' is not recognized as an internal or external command, operable program or batch file." is written to console window

    int no_spaces_backward_rc = std::system("c:\\IronPython2.7\\ipy -c \"print 'no_spaces_backward'\"");
    // no_spaces_backward_rc is 0 and "no_spaces_backward" is written to console window

    int spaces_backward_rc    = std::system("\"c:\\Program Files (x86)\\IronPython 2.7\\ipy\" -c \"print 'spaces_backward'\"");
    // spaces_backward_rc is 1, and "'c:\Program' is not recognized as an internal or external command, operable program or batch file." is written to console window

    int no_spaces_double_backward_rc = std::system("c:\\\\IronPython2.7\\\\ipy -c \"print 'no_spaces_double_backward'\"");
    // no_spaces_double_backward_rc is 0, and no_spaces_double_backward is written to console window

    int spaces_double_backward_rc    = std::system("\"c:\\\\Program Files (x86)\\\\IronPython 2.7\\\\ipy\" -c \"print 'spaces_double_backward'\"");
    // spaces_double_backward_rc is 1, and "'c:\\Program' is not recognized as an internal or external command, operable program or batch file." is written to console window

    int spaces_double_double_backward_rc    = std::system("\\\"c:\\\\Program Files (x86)\\\\IronPython 2.7\\\\ipy\\\" -c \"print 'spaces_double_double_backward'\"");
    // spaces_dobule_double_backward_rc is 1, and "'\"c:\\Program Files (x86)\\IronPython 2.7\\ipy\"' is not recognized as an internal or external command, operable program or batch file." is written to console window

    return 0;
}

我已经确认直接在cmd提示符下运行"c:\Program Files (x86)\IronPython 2.7\ipy" -c "print 'spaces_backward'"是有效的，而且我很确定我不会有错字。这让我疯了 - 任何帮助都会非常感激！

（我使用Visual Studio 2012并使用子系统控制台进行编译，如果有帮助的话。）

Answer 1

cmd.exe的语法有一个令人讨厌的转折。来自cmd.exe /?：

1.  If all of the following conditions are met, then quote characters
    on the command line are preserved:

    - no /S switch
    - exactly two quote characters
    - no special characters between the two quote characters,
      where special is one of: &<>()@^|
    - there are one or more whitespace characters between the
      two quote characters
    - the string between the two quote characters is the name
      of an executable file.

要使行为保持一致，std::system调用应使用/S开关，并将命令嵌入引号中。可悲的是，它没有。这意味着这将起作用：

std::system("\"c:\\Program Files (x86)\\Adobe\\Reader 10.0\\Reader\\AcroRd32.exe\" h:\\documents\\documentation\\misc\\calendar 1999.pdf");

但这个看似微不足道的变种赢了：

std::system("\"c:\\Program Files (x86)\\Adobe\\Reader 10.0\\Reader\\AcroRd32.exe\" \"h:\\documents\\documentation\\misc\\calendar 1999.pdf\"");

要解决此问题，整个命令包括可执行文件的引用路径，必须用引号括起来：

std::system("\"\"c:\\Program Files (x86)\\Adobe\\Reader 10.0\\Reader\\AcroRd32.exe\" \"h:\\documents\\documentation\\misc\\calendar 1999.pdf\"\"");

在您的示例中，那将是

std::system("\"\"c:\\Program Files (x86)\\IronPython 2.7\\ipy\" -c \"print 'spaces_backward'\"\"");

Answer 2

使用raw string literal确定此代码，实际上适用于我（VS2013 Express）：

std::string cmd = R"cmd("C:\Program Files (x86)\doxygen\bin\doxygen.exe")cmd";
system(cmd.c_str());

对于不受支持的原始字符串文字，传统的转义字符串文字应如下所示1：

std::string cmd = "\"C:\\Program Files (x86)\\doxygen\\bin\\doxygen.exe\"";

这些双重转义的原因是system()实际调用cmd，它需要双引号"来封闭命令行来执行。

_{1）很容易看到，在某处错过\很容易出错。}

如何在Windows上使用std :: system运行带空格的可执行文件

2 个答案: